[jdk17u-dev] RFR: 8283279: [Testbug] Improve TestGetSwapSpaceSize

[Severin Gehwolf]

Test fix which now asserts some pre-conditions. Applies clean.

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Commit messages:
 - Backport a77160065bb6f62314711514f7694fe50f0dc35b

Changes: https://git.openjdk.java.net/jdk17u-dev/pull/339/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u-dev&pr=339&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8283279
  Stats: 31 lines in 2 files changed: 22 ins; 1 del; 8 mod
  Patch: https://git.openjdk.java.net/jdk17u-dev/pull/339.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u-dev pull/339/head:pull/339

PR: https://git.openjdk.java.net/jdk17u-dev/pull/339