RFR: 8357218: G1: Remove loop in G1CollectedHeap::try_collect_fullgc [v3]

[Albert Mingkun Yang]

> Simple removing unnecessary loop in "caller" of `VM_G1CollectFull`, because an explicit full-gc always run-to-completion.
> 
> Test: tier1-3

Albert Mingkun Yang has updated the pull request incrementally with one additional commit since the last revision:

  review

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Changes:
  - all: https://git.openjdk.org/jdk/pull/25296/files
  - new: https://git.openjdk.org/jdk/pull/25296/files/722aac36..666cc5a1

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25296&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25296&range=01-02

  Stats: 10 lines in 3 files changed: 4 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/25296.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25296/head:pull/25296

PR: https://git.openjdk.org/jdk/pull/25296