RFR: 8331061: Serial: Missed BOT update in TenuredGeneration::expand_and_allocate

[Albert Mingkun Yang]

Add the missed BOT update for allocations in old-gen.

Test succeeds with the fix.

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Commit messages:
 - bot-fix

Changes: https://git.openjdk.org/jdk/pull/18936/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18936&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8331061
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/18936.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18936/head:pull/18936

PR: https://git.openjdk.org/jdk/pull/18936