Restrict to valid Argon2 algorithms only

[prd-fox]

Throw an exception if an invalid Argon2 algorithm is encountered.
This is to ensure the user is aware that they are doing something improper and for them to correct it instead of doing something they may not want.

[codecov-io]

Codecov Report

Merging #531 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master     #531      +/-   ##
============================================
- Coverage     99.42%   99.41%   -0.01%     
+ Complexity     1257     1235      -22     
============================================
  Files           211      209       -2     
  Lines          3975     3927      -48     
  Branches        212      210       -2     
============================================
- Hits           3952     3904      -48     
  Misses            5        5              
  Partials         18       18

Impacted Files	Coverage Δ	Complexity Δ
...ain/java/com/quorum/tessera/argon2/Argon2Impl.java	100% <100%> (ø)	8 <0> (+1)	⬆️
.../com/quorum/tessera/node/PartyInfoServiceImpl.java	100% <0%> (ø)	13% <0%> (ø)	⬇️
...in/java/com/quorum/tessera/api/ConfigResource.java	100% <0%> (ø)	5% <0%> (ø)	⬇️
.../quorum/tessera/config/keypairs/DirectKeyPair.java	100% <0%> (ø)	5% <0%> (ø)	⬇️
...main/java/com/quorum/tessera/node/model/Party.java	100% <0%> (ø)	6% <0%> (-1%)	⬇️
.../java/com/quorum/tessera/node/PartyInfoParser.java	100% <0%> (ø)	8% <0%> (-12%)	⬇️
...rum/tessera/config/keypairs/FilesystemKeyPair.java	100% <0%> (ø)	12% <0%> (ø)	⬇️
.../quorum/tessera/config/keypairs/InlineKeypair.java	100% <0%> (ø)	7% <0%> (ø)	⬇️
...sera/config/constraints/ValidContentValidator.java
.../quorum/tessera/node/PartyInfoParserException.java

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