[jdk8u-dev] RFR: 8295950: Enable langtools/tier1 in GHA for 8u

[zzambers]

It is now possible to enable langtools/tier1 in Github actions for jdk8u as the only failure there has been resolved [1].

[1] https://bugs.openjdk.org/browse/JDK-8265527

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Commit messages:
 - Enabled langtools/tier1 in GHA

Changes: https://git.openjdk.org/jdk8u-dev/pull/149/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=149&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8295950
  Stats: 15 lines in 1 file changed: 0 ins; 0 del; 15 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/149.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev pull/149/head:pull/149

PR: https://git.openjdk.org/jdk8u-dev/pull/149