Disallow CORS to be configured on anything but ThirdParty server

[namtruong]

Allowing CORS config on other types of server such as P2P carry potential security issues

[codecov-io]

Codecov Report

Merging #917 into master will decrease coverage by 0.01%.
The diff coverage is 94.11%.

@@             Coverage Diff              @@
##             master     #917      +/-   ##
============================================
- Coverage     99.37%   99.35%   -0.02%     
- Complexity     2093     2094       +1     
============================================
  Files           318      318              
  Lines          5761     5772      +11     
  Branches        308      310       +2     
============================================
+ Hits           5725     5735      +10     
  Misses            5        5              
- Partials         31       32       +1

Impacted Files	Coverage Δ	Complexity Δ
...sera/config/constraints/ServerConfigValidator.java	95.83% <94.11%> (-4.17%)	6 <4> (+1)
.../tessera/admin/cli/subcommands/AddPeerCommand.java	97.36% <0%> (ø)	11% <0%> (ø)	⬇️
.../quorum/tessera/sync/SyncResponseMessageCodec.java	96.77% <0%> (ø)	5% <0%> (ø)	⬇️
...ain/java/com/quorum/tessera/p2p/RestP2pClient.java	93.1% <0%> (ø)	9% <0%> (ø)	⬇️

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