[improve][txn]Add log when can't send TcClientConnectRequest to broker.

[liangyepianzhou]

Main Issue: #20851

Motivation

When the Proto version does not allow us to send TcClientConnectRequest to the broker, we should add a log to debug it.

Modifications

Add a waining log.

Verifying this change

• Make sure that the change passes the CI checks.

(Please pick either of the following options)

This change is a trivial rework / code cleanup without any test coverage.

(or)

This change is already covered by existing tests, such as (please describe tests).

(or)

This change added tests and can be verified as follows:

(example:)

• Added integration tests for end-to-end deployment with large payloads (10MB)
• Extended integration test for recovery after broker failure

Does this pull request potentially affect one of the following parts:

If the box was checked, please highlight the changes

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository:

[codecov-commenter]

Codecov Report

Merging #20880 (8ebfd77) into master (69d7a2b) will decrease coverage by 0.09%.
Report is 10 commits behind head on master.
The diff coverage is 81.08%.

@@             Coverage Diff              @@
##             master   #20880      +/-   ##
============================================
- Coverage     73.17%   73.08%   -0.09%     
+ Complexity    32231    32230       -1     
============================================
  Files          1874     1874              
  Lines        139302   139379      +77     
  Branches      15322    15328       +6     
============================================
- Hits         101934   101865      -69     
- Misses        29311    29462     +151     
+ Partials       8057     8052       -5     

Flag	Coverage Δ
inttests	24.15% <50.00%> (-0.27%)	⬇️
systests	25.06% <50.00%> (-0.14%)	⬇️
unittests	72.38% <81.08%> (-0.08%)	⬇️

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

Files Changed	Coverage Δ
...he/pulsar/broker/resources/NamespaceResources.java	80.71% <ø> (-0.72%)	⬇️
...broker/service/persistent/DispatchRateLimiter.java	81.48% <ø> (ø)
...roker/service/persistent/SubscribeRateLimiter.java	58.76% <ø> (ø)
...ulsar/client/impl/TransactionMetaStoreHandler.java	68.12% <0.00%> (-0.09%)	⬇️
...rg/apache/pulsar/broker/service/AbstractTopic.java	87.03% <66.66%> (-1.70%)	⬇️
...roker/loadbalance/impl/ModularLoadManagerImpl.java	81.60% <76.00%> (-0.20%)	⬇️
...rg/apache/pulsar/broker/service/BrokerService.java	80.96% <78.57%> (-0.95%)	⬇️
...va/org/apache/pulsar/broker/service/ServerCnx.java	71.28% <93.02%> (+0.14%)	⬆️
...oker/service/nonpersistent/NonPersistentTopic.java	73.27% <100.00%> (-1.02%)	⬇️
...sar/broker/service/persistent/PersistentTopic.java	79.39% <100.00%> (-0.16%)	⬇️

... and 61 files with indirect coverage changes