RFR: 8543: Minor discrepancies between Oracle JMC and Open JMC

[Suchita Chaturvedi]

This PR is addressing the Minor discrepancies between Oracle JMC and Open JMC.

- Few accessibility related changes.
- Some JDK and eclipse version changes in help pages.
- Few links are updated from http to https.
- Copyright year changes.
- Owasp Encoder was updated to 1.2.3 but license was still mentioning 1.2.2 updated that as well.

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Commit messages:
 - 8543: Minor discrepancies between Oracle JMC and Open JMC

Changes: https://git.openjdk.org/jmc/pull/710/files
  Webrev: https://webrevs.openjdk.org/?repo=jmc&pr=710&range=00
  Issue: https://bugs.openjdk.org/browse/JMC-8543
  Stats: 196 lines in 16 files changed: 154 ins; 0 del; 42 mod
  Patch: https://git.openjdk.org/jmc/pull/710.diff
  Fetch: git fetch https://git.openjdk.org/jmc.git pull/710/head:pull/710

PR: https://git.openjdk.org/jmc/pull/710