chore(deps): update actions/checkout action to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v2 -> v4

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Release Notes

actions/checkout (actions/checkout)

v4

Compare Source

• Support fetching without the --progress option
• Update to node20

v3

Compare Source

• Fix: Mark test scripts with Bash'isms to be run via Bash
• Add option to fetch tags even if fetch-depth > 0

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[github-actions]

Sadly there were some test failures on 'That Ubuntu test machine':

The following tests FAILED:
	 69 - tst_platformhelperstest (Timeout)

69: FAIL!  : PlatformHelpersTest::requireThat_parallellExportSucceeds() Compared values are not the same
69:    Actual   ((messages.size())) : 0
69:    Expected (outputPaths.size()): 5
69:    Loc: [../unittests/platformhelperstest.cpp(154)]