Rename fork e2e job into e2e-fork. (cosmos#3827)

* Rename fork e2e job into e2e-fork, document.

Author: DimitrisJim

.github/workflows/e2e-fork.yml

@@ -26,7 +26,8 @@ jobs:
         env:
           TEST_EXCLUSIONS: 'TestInterTxTestSuite,TestIncentivizedInterTxTestSuite,TestUpgradeTestSuite'
 
-  e2e:
+  # e2e-fork runs the e2e tests directly by using a matrix strategy.
+  e2e-fork:
     env:
       CHAIN_A_TAG: latest
       CHAIN_B_TAG: latest

.github/workflows/e2e.yaml

@@ -75,6 +75,8 @@ jobs:
               fi
           done
 
+  # e2e generates the e2e tests for the non-forked PRs. It does so by using the
+  # e2e-test-workflow-call.yml each test runs the jobs defined in that file.
   e2e:
     # we will be running this job if the PR has not yet been marked for review, and we push additional changes.
     # we skip the job in this case.