Refactor rpc utils test

[gzhao9]

What is the purpose of the change

Similarly, to #13153, I noticed that in RpcUtilsTest, there is also a duplicate creation of the mock.

The Invoker was duplicated to create the mock object 10 times, in 10 test cases.
I used a similar approach refactoring to increase code readability.

Brief changelog

I refactored the code to introduce two methods: CreateMockInvoker(URL url) and CreateMockInvoker(). I've used these methods in 10 test cases to reduce the repetitive creation of the Invoker mock.

Additional questions.

I also noticed that this pattern appears in different test files for different packages, do you prefer to use shared utility classes or define these methods in each file?

Verifying this change

Checklist

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[codecov-commenter]

Codecov Report

Merging #13214 (9b18e3e) into 3.2 (a4a3fd7) will increase coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##                3.2   #13214   +/-   ##
=========================================
  Coverage     69.44%   69.45%           
  Complexity        2        2           
=========================================
  Files          1649     1649           
  Lines         68725    68725           
  Branches      10014    10014           
=========================================
+ Hits          47728    47733    +5     
+ Misses        16405    16399    -6     
- Partials       4592     4593    +1     

see 36 files with indirect coverage changes

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[AlbumenJ]

Also fix in your code

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication