Save and restore skeleton dir for integration and UI tests

[phil-davis]

Description

When starting integration or UI tests, remember the previous value of skeletondirectory
At the end, out it back
Remove the now-unneeded setting of skeletondirectory in preseed-config.php

Related Issue

#28602

Motivation and Context

Make life easier for development manual runs of integration and UI tests

How Has This Been Tested?

1. Set skeletondirectory to some "random" string
2. Run some UI tests - make sure they work
3. Check that skeletondirectory keeps its value
4. Run some integration tests - make sure they work
5. Check that skeletondirectory keeps its value

Repeat with skeletondirectory undefined, make sure it stays undefined after each test run.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[individual-it]

looks good and usefull

[individual-it]

backport to stable10?

[phil-davis]

Backport in #28610

[individual-it]

we could not get rid of the line "skeletondirectory set to /tests/ui/skeleton." in https://github.com/owncloud/documentation/blob/master/developer_manual/core/ui-testing.rst or not?

[phil-davis]

Doc update in owncloud-archive/documentation#3288

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.