RFR: 8354343: Hardening of Currency tests for not yet defined future ISO 4217 currency [v2]

[Justin Lu]

> Please review this PR which improves future currency checking for ISO 4217 currencies.
> 
> Checking for a currency that should not yet exist in the set of available currencies is already done.
> It should also be explicitly checked that such a currency can not be instantiated as well via the String getter.

Justin Lu has updated the pull request incrementally with one additional commit since the last revision:

  move future currencies set up under setUpTestingData()

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/24782/files
  - new: https://git.openjdk.org/jdk/pull/24782/files/7424e964..6c4cbe94

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24782&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24782&range=00-01

  Stats: 3 lines in 1 file changed: 1 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/24782.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24782/head:pull/24782

PR: https://git.openjdk.org/jdk/pull/24782