[jdk20u] RFR: 8305750: Typo in shenandoahSupport.cpp

[William Kemper]

`isNeverBranch` should be `is_NeverBranch`.

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Commit messages:
 - Fix typo, fix build error

Changes: https://git.openjdk.org/jdk20u/pull/52/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk20u&pr=52&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305750
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk20u/pull/52.diff
  Fetch: git fetch https://git.openjdk.org/jdk20u.git pull/52/head:pull/52

PR: https://git.openjdk.org/jdk20u/pull/52