RFR: 8311514: Incorrect regex in TestMetaSpaceLog.java [v3]

[Daohan Qu]

> The regex in jtreg test `TestMetaSpaceLog.java` is intended to capture the metaspace size before and after the reclamation. But it captures the wrong value. which might cause this test to always pass. The results of the capture can be displayed using a visualization tool.
> 
> Before this patch:
> <img width="1128" alt="屏幕快照 2023-07-06 17 18 15" src="https://github.com/openjdk/jdk/assets/18374295/4e3b6606-24b3-4d7f-a70d-f312cb867fbf">
> 
> After this patch:
> <img width="1125" alt="屏幕快照 2023-07-06 17 18 25" src="https://github.com/openjdk/jdk/assets/18374295/b100018e-2c39-4154-9ec7-80e5eedc212e">

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

  Fix the bug of not matching another type of metaspace change log and build the regex incrementally

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/14782/files
  - new: https://git.openjdk.org/jdk/pull/14782/files/cb7b216f..68c1a652

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14782&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14782&range=01-02

  Stats: 6 lines in 1 file changed: 3 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/14782.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14782/head:pull/14782

PR: https://git.openjdk.org/jdk/pull/14782