[jdk16u] RFR: 8260356: (tz) Upgrade time-zone data to tzdata2021a

[Kiran Sidhartha Ravikumar]

tzdata2021a integration to jdk16u.

Passed regression and applies clean

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Commit messages:
 - Backport d9aefa36ac1d4b711a3082e3ce6c442d4cb8e718

Changes: https://git.openjdk.java.net/jdk16u/pull/22/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk16u&pr=22&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8260356
  Stats: 12 lines in 3 files changed: 6 ins; 0 del; 6 mod
  Patch: https://git.openjdk.java.net/jdk16u/pull/22.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk16u pull/22/head:pull/22

PR: https://git.openjdk.java.net/jdk16u/pull/22