RFR: 8341927: Replace hardcoded security providers with new test.provider.name system property [v6]

[Matthew Donovan]

> In this PR, I removed hard-coded security providers and replaced them with a system property, test.provider.name. If the property is not specified, the provider originally used in the test is used:
> 
> Cipher c = Cipher.getInstance("AES/GCM/NoPadding", System.getProperty("test.provider.name", "SunJCE"));

Matthew Donovan has updated the pull request incrementally with one additional commit since the last revision:

  updated testing doc per PR comments

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Changes:
  - all: https://git.openjdk.org/jdk/pull/21551/files
  - new: https://git.openjdk.org/jdk/pull/21551/files/3999bb84..3889e339

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21551&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21551&range=04-05

  Stats: 30 lines in 2 files changed: 0 ins; 14 del; 16 mod
  Patch: https://git.openjdk.org/jdk/pull/21551.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21551/head:pull/21551

PR: https://git.openjdk.org/jdk/pull/21551