RFR: 8372149: G1: Remove unnecessary num_added_to_group from G1CollectionSetCandidates::set_candidates_from_marking()

[Thomas Schatzl]

Hi all,

  please review this tiny change to remove some local variable (and management) in G1. The one use of the getter from the container is just as easy to understand to me (vs. declaration and management).

Testing: gha

Thanks,
  Thomas

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Commit messages:
 - 8372149

Changes: https://git.openjdk.org/jdk/pull/28419/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28419&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8372149
  Stats: 5 lines in 1 file changed: 0 ins; 4 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/28419.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28419/head:pull/28419

PR: https://git.openjdk.org/jdk/pull/28419