Enabled spring RestTemplate tests for spring 6

[JonasKunz]

What does this PR do?

Extended the Spring RestTemplate integration tests to test with spring 6 if the JVM version is at least 17.

Checklist

• This is something else
  • I have updated CHANGELOG.asciidoc

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Build stats

• Start Time: 2022-12-14T10:39:15.778+0000

• Duration: 62 min 28 sec

Test stats 🧪

Test	Results
Failed	0
Passed	3236
Skipped	42
Total	3278

💚 Flaky test report

Tests succeeded.

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