Update actions/checkout action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v5.0.1 -> v6.0.0
actions/checkout	action	major	v5 -> v6

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Release Notes

actions/checkout (actions/checkout)

v6.0.0

Compare Source

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Configuration

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
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0.0% Coverage on New Code
0.0% Duplication on New Code

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