bugfix: fix readonly branch commit errors in Oracle XA transactions.

[gongycn]

• I have registered the PR changes.

Ⅰ. Describe what this PR did

fix the issue of readonly branch commit errors in Oracle XA transactions, which leads to long-running transactions being unable to commit and causing unreadable states.
Solution Logic:
When the database is Oracle and the prepare result is XA_RDONLY, notify TC that the current branch status is BranchStatus.PhaseOne_RDONLY (a newly added state to address this issue). During global commit, for branches with this status type, delete the branch log directly and ignore it.

Ⅱ. Does this pull request fix one issue?

fixes #6512
Original pull request: #6629

Ⅲ. Why don't you add test cases (unit test/integration test)?

Ⅳ. Describe how to verify it

Based on the problematic local project instance, the verification includes:

Whether the Seata TC frontend displays normally;
In Seata TM managing multiple RMs, whether it functions correctly when there is one or more readonly branches; whether it functions correctly when there are no readonly branches; and whether it functions correctly when there are only one or more readonly branches.

Ⅴ. Special notes for reviews

[gongycn]

@funky-eyes Accidentally closed #6629 due to misoperation, resubmitted here.

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 6 lines in your changes missing coverage. Please review.

Project coverage is 50.47%. Comparing base (7d3cf99) to head (484cc78).

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x    #6707      +/-   ##
============================================
- Coverage     50.47%   50.47%   -0.01%     
+ Complexity     5831     5830       -1     
============================================
  Files          1051     1051              
  Lines         36340    36347       +7     
  Branches       4319     4325       +6     
============================================
+ Hits          18342    18345       +3     
+ Misses        16183    16181       -2     
- Partials       1815     1821       +6     

Files	Coverage Δ
...java/org/apache/seata/core/model/BranchStatus.java	100.00% <100.00%> (ø)
...ache/seata/rm/datasource/xa/ConnectionProxyXA.java	55.68% <33.33%> (-0.68%)	⬇️
...g/apache/seata/server/coordinator/DefaultCore.java	47.15% <0.00%> (-1.10%)	⬇️

... and 3 files with indirect coverage changes

[funky-eyes]

LGTM