RFR: 8284026: Use unmodifiable collections where practical [v2]

[Pavel Rappo]

> New code in jdk.javadoc tends to use `{List, Set, Map}.of` methods instead of similar methods from `Collections`, which are used in the existing jdk.javadoc code. Having a mix of these two families of methods is distracting. This PR upgrades existing code to `{List, Set, Map}.of` methods where practical.

Pavel Rappo has updated the pull request incrementally with one additional commit since the last revision:

  Remove some `@see` tags
  
  At a minimum, some of those `@see` tags are no longer relevant. But generally speaking, in this day and age and this codebase, those @see tags are silly.

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8046/files
  - new: https://git.openjdk.java.net/jdk/pull/8046/files/e733dc7c..bc21384d

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8046&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8046&range=00-01

  Stats: 4 lines in 1 file changed: 0 ins; 4 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8046.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8046/head:pull/8046

PR: https://git.openjdk.java.net/jdk/pull/8046