[jdk17u-dev] RFR: 8294740: Add cgroups keyword to TestDockerBasic.java

[Severin Gehwolf]

Clean backport. Just adds a `@cgroups` tag to a test added with #785.

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Depends on: https://git.openjdk.org/jdk17u-dev/pull/785

Commit messages:
 - Backport ae79af2ad67b51a7608f4c9060421dd175cabf3f

Changes: https://git.openjdk.org/jdk17u-dev/pull/795/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=795&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8294740
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/795.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/795/head:pull/795

PR: https://git.openjdk.org/jdk17u-dev/pull/795