RFR: 8340493: Fix some Asserts failure messages [v3]

[Weijun Wang]

> `Asserts.assertNotEquals` shows "expected 12345 to not equal 12345" which sounds redundant, just say "expected not equals but was 12345".
> 
> `Asserts.assertEqualsByteArray` uses the words "expected... to equal...". Modify it to follow the `assertEquals` style ""expected... but was...".

Weijun Wang has updated the pull request incrementally with one additional commit since the last revision:

  be precise in method spec

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/21101/files
  - new: https://git.openjdk.org/jdk/pull/21101/files/5c5c2a3a..8f06ba16

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21101&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21101&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/21101.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21101/head:pull/21101

PR: https://git.openjdk.org/jdk/pull/21101