RFR: 8349771: Replace usages of -mx and -ms in some monitor tests [v2]

[SendaoYan]

> Hi all,
> This PR updates two runtime/Monitor tests to replace the usage of the outdated `-mx` and `-ms` java launcher options with `-Xmx` and `-Xms`.
> 
> As noted in [JDK-8349771](https://bugs.openjdk.org/browse/JDK-8349771), these outdated options will soon be deprecated for removal from the java launcher code.
> 
> Change has been verified locally, test-fix only, no risk.

SendaoYan has updated the pull request incrementally with one additional commit since the last revision:

  Add missing comma in file header

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23553/files
  - new: https://git.openjdk.org/jdk/pull/23553/files/c016265e..844cda3b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23553&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23553&range=00-01

  Stats: 2 lines in 2 files changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/23553.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23553/head:pull/23553

PR: https://git.openjdk.org/jdk/pull/23553