[jdk21u-dev] RFR: Merge jdk21u:master

[Goetz Lindenmaier]

Merge build tag 21.0.8-ga from jdk21u to jdk21u-dev

-------------

Commit messages:
 - Merge
 - 8361672: [21u] Remove designator DEFAULT_PROMOTED_VERSION_PRE=ea for release 21.0.8
 - 8360147: Better Glyph drawing redux
 - 8350991: Improve HTTP client header handling
 - 8349594: Enhance TLS protocol support
 - 8349111: Enhance Swing supports
 - 8348989: Better Glyph drawing
 - 8345625: Better HTTP connections

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1979&range=00.0
 - jdk21u:master: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1979&range=00.1

Changes: https://git.openjdk.org/jdk21u-dev/pull/1979/files
  Stats: 302 lines in 18 files changed: 217 ins; 22 del; 63 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1979.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1979/head:pull/1979

PR: https://git.openjdk.org/jdk21u-dev/pull/1979