[No QA] Update CONTRIBUTING.md and PR Template to cover High Traffic / Offline

.github/PULL_REQUEST_TEMPLATE.md

@@ -36,6 +36,11 @@ For example:
 
 - [ ] Verify that no errors appear in the JS console
 
+### Offline tests
+<!---
+Add any relevant steps that validate your changes work as expected in a variety of network states e.g. "offline", "spotty connection", "slow internet", etc. Manual test steps should be written so that your reviewer and QA testers can repeat and verify one or more expected outcomes. If you are unsure how the behavior should work ask for advice in the `#expensify-open-source` Slack channel.
+--->
+
 ### QA Steps
 <!---
 Add a numbered list of manual tests that can be performed by our QA engineers on the staging environment to validate that your changes work on all platforms, and that there are no regressions present.
@@ -58,9 +63,12 @@ This is a checklist for PR authors. Please make sure to complete all tasks and c
 - [ ] I linked the correct issue in the `### Fixed Issues` section above
 - [ ] I wrote clear testing steps that cover the changes made in this PR
     - [ ] I added steps for local testing in the `Tests` section
+    - [ ] I added steps for the expected offline behavior in the `Offline steps` section
     - [ ] I added steps for Staging and/or Production testing in the `QA steps` section
     - [ ] I added steps to cover failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
     - [ ] I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
+    - [ ] I tested this PR with a [High Traffic account](https://github.com/Expensify/App/blob/main/contributingGuides/CONTRIBUTING.md#high-traffic-accounts) against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
+
 - [ ] I included screenshots or videos for tests on [all platforms](https://github.com/Expensify/App/blob/main/contributingGuides/CONTRIBUTING.md#make-sure-you-can-test-on-all-platforms)
 - [ ] I ran the tests on **all platforms** & verified they passed on:
     - [ ] iOS / native
@@ -110,9 +118,11 @@ The reviewer will copy/paste it into a new comment and complete it after the aut
 - [ ] I verified the correct issue is linked in the `### Fixed Issues` section above
 - [ ] I verified testing steps are clear and they cover the changes made in this PR
     - [ ] I verified the steps for local testing are in the `Tests` section
+    - [ ] I verified the steps for expected offline behavior are in the `Offline steps` section
     - [ ] I verified the steps for Staging and/or Production testing are in the `QA steps` section
     - [ ] I verified the steps cover any possible failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
     - [ ] I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
+    - [ ] I tested this PR with a [High Traffic account](https://github.com/Expensify/App/blob/main/contributingGuides/CONTRIBUTING.md#high-traffic-accounts) against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
 - [ ] I checked that screenshots or videos are included for tests on [all platforms](https://github.com/Expensify/App/blob/main/contributingGuides/CONTRIBUTING.md#make-sure-you-can-test-on-all-platforms)
 - [ ] I included screenshots or videos for tests on [all platforms](https://github.com/Expensify/App/blob/main/contributingGuides/CONTRIBUTING.md#make-sure-you-can-test-on-all-platforms)
 - [ ] I verified tests pass on **all platforms** & I tested again on:

contributingGuides/CONTRIBUTING.md

@@ -15,6 +15,9 @@ You can create as many accounts as needed in order to test your changes directly
 ##### Generating Multiple Test Accounts
 You can generate multiple test accounts by using a `+` postfix, for example if your email is test@test.com, you can create multiple New Expensify accounts connected to the same email address by using test+123@test.com, test+456@test.com, etc.
 
+##### High Traffic Accounts
+All internal engineers, contributors, and C+ members are **required** to test with a "high traffic" account against the staging or production web servers. Ask in [#expensify-open-source](https://expensify.slack.com/archives/C01GTK53T8Q) if someone can turn your account into a High Traffic account. These accounts more closely mirror the accounts used in production by real people. Internal team members can follow [this Stack Overflow](https://stackoverflow.com/c/expensify/questions/14504) to upgrade an account.
+
 #### Working on beta features
 Some features are locked behind beta flags while development is ongoing. As a contributor you can work on these beta features locally by overriding the [`Permissions.canUseAllBetas` function](https://github.com/Expensify/App/blob/5e268df7f2989ed04bc64c0c86ed77faf134554d/src/libs/Permissions.js#L10-L12) to return `true`.