[improve][broker] Add test to verify authRole cannot change

[michaeljmarshall]

Motivation

While working on #19409, I noticed we do not have any tests in the ServerCnxTests class verifying the authRole cannot change. This seems like an oversight, and this PR adds tests to assert the existing behavior works as intended.

Modifications

• Add new test AuthenticationProvider and AuthenticationState implementations to simplify testing
• Add two tests to verify the behavior that a connection is closed when the authRole changes.

Verifying this change

This change is to add tests.

Documentation

• doc-not-needed

Matching PR in forked repository

PR in forked repository: Skipping testing in my fork since these are new tests and I got them to pass locally.

[lhotari]

Good work @michaeljmarshall

[codecov-commenter]

Codecov Report

Merging #19430 (3c8ef5e) into master (7449baa) will increase coverage by 0.02%.
The diff coverage is 81.25%.

@@             Coverage Diff              @@
##             master   #19430      +/-   ##
============================================
+ Coverage     62.63%   62.66%   +0.02%     
- Complexity    25752    25768      +16     
============================================
  Files          1832     1832              
  Lines        134053   134067      +14     
  Branches      14752    14753       +1     
============================================
+ Hits          83967    84014      +47     
+ Misses        42346    42340       -6     
+ Partials       7740     7713      -27     

Flag	Coverage Δ
inttests	24.85% <43.75%> (+0.01%)	⬆️
systests	25.42% <43.75%> (-0.01%)	⬇️
unittests	59.90% <81.25%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...rg/apache/pulsar/client/impl/PulsarClientImpl.java	73.65% <ø> (-1.21%)	⬇️
.../client/admin/internal/PulsarAdminBuilderImpl.java	87.67% <78.57%> (-2.16%)	⬇️
...g/apache/pulsar/client/impl/ClientBuilderImpl.java	80.27% <78.57%> (-0.18%)	⬇️
.../pulsar/client/admin/internal/PulsarAdminImpl.java	80.58% <100.00%> (+3.22%)	⬆️
...lsar/client/impl/conf/ClientConfigurationData.java	96.61% <100.00%> (-0.06%)	⬇️
...a/org/apache/pulsar/client/impl/TableViewImpl.java	61.66% <0.00%> (-24.17%)	⬇️
...va/org/apache/pulsar/common/util/NumberFormat.java	66.66% <0.00%> (-12.50%)	⬇️
.../pulsar/broker/service/SharedConsumerAssignor.java	70.37% <0.00%> (-9.26%)	⬇️
...pache/pulsar/client/impl/TableViewBuilderImpl.java	79.31% <0.00%> (-6.90%)	⬇️
...e/pulsar/common/naming/NamespaceBundleFactory.java	55.55% <0.00%> (-3.89%)	⬇️
... and 73 more

[michaeljmarshall]

I cherry picked this test because it is valid for all release branches and it ensured correctness for some of my cherry picked changes, which is very valuable.