<i18n dev> RFR: 8274407: (tz) Update Timezone Data to 2021c

[Naoto Sato]

This PR is to upgrade the time zone data in the JDK to IANA's tzdata2021c level. Note that the tz data is "as is", as released by IANA. No `merged links` are retracted.
The PR also fixes two issues along with the 2021c upgrade.

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Commit messages:
 - Fix for Asia/Amman test case error
 - Test fix for Samoa not observing DST
 - tzdata2021c
 - 8274407: (tz) Update Timezone Data to 2021b

Changes: https://git.openjdk.java.net/jdk/pull/5832/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5832&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274407
  Stats: 635 lines in 13 files changed: 228 ins; 329 del; 78 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5832.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5832/head:pull/5832

PR: https://git.openjdk.java.net/jdk/pull/5832