[fix][test] broker.admin.PersistentTopicsTest#testUnloadTopic

[labuladong]

Fixes #19265

Modifications

Reset mock object before reuse.

Verifying this change

• Make sure that the change passes the CI checks.

Documentation

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

[codecov-commenter]

Codecov Report

Merging #19347 (8ec2fb1) into master (c875365) will decrease coverage by 0.64%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master   #19347      +/-   ##
============================================
- Coverage     63.28%   62.64%   -0.64%     
- Complexity     3583    26225   +22642     
============================================
  Files          1893     1895       +2     
  Lines        137452   137529      +77     
  Branches      15091    15098       +7     
============================================
- Hits          86982    86154     -828     
- Misses        42615    43410     +795     
- Partials       7855     7965     +110     

Flag	Coverage Δ
inttests	23.97% <ø> (-0.07%)	⬇️
systests	24.80% <ø> (-0.06%)	⬇️
unittests	60.56% <ø> (-0.47%)	⬇️

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

Impacted Files	Coverage Δ
...g/apache/pulsar/client/api/ServiceUrlProvider.java	0.00% <0.00%> (-100.00%)	⬇️
...lsar/client/impl/auth/AuthenticationDataBasic.java	0.00% <0.00%> (-100.00%)	⬇️
.../stats/prometheus/AggregatedSubscriptionStats.java	0.00% <0.00%> (-100.00%)	⬇️
...metheus/AggregatedTransactionCoordinatorStats.java	0.00% <0.00%> (-100.00%)	⬇️
...broker/stats/prometheus/TransactionAggregator.java	0.00% <0.00%> (-96.06%)	⬇️
.../impl/auth/oauth2/AuthenticationFactoryOAuth2.java	0.00% <0.00%> (-88.89%)	⬇️
.../apache/pulsar/utils/CmdGenerateDocumentation.java	0.00% <0.00%> (-76.93%)	⬇️
...ker/stats/prometheus/AggregatedNamespaceStats.java	5.20% <0.00%> (-76.05%)	⬇️
...ar/broker/stats/prometheus/ManagedLedgerStats.java	28.57% <0.00%> (-71.43%)	⬇️
...e/pulsar/client/impl/auth/AuthenticationBasic.java	0.00% <0.00%> (-69.24%)	⬇️
... and 212 more