test(microprofile): replace fixed sleeps with mirror-node polling in integration tests

[alejandroGM0]

Problem

Several MicroProfile integration tests use a hard-coded Thread.sleep(10_000) before
querying the mirror node:

• AccountRepositoryTest – 1 occurrence
• TokenRepositoryTest – 6 occurrences
• TopicRepositoryTest – 4 occurrences

Each call has a // TODO: fix sleep comment acknowledging the issue. Fixed sleeps have
two drawbacks:

1. Slow – always waits the full 10 s even when the mirror node has already indexed the
   record.
2. Flaky – may still time out when the mirror node is under load or the network is slow.

The Spring integration tests already use HieroTestUtils.waitForMirrorNodeRecords(),
which polls until the last submitted transaction appears in the mirror node (or times out),
making them faster on a healthy network and more reliable under load.

Expected behaviour

All MicroProfile integration tests replace Thread.sleep(10_000) with
hieroTestUtils.waitForMirrorNodeRecords(), consistent with the Spring test suite.

Scope

• hiero-enterprise-microprofile/.../AccountRepositoryTest.java
• hiero-enterprise-microprofile/.../TokenRepositoryTest.java
• hiero-enterprise-microprofile/.../TopicRepositoryTest.java

[github-actions]

Thanks for your submission.

This issue is awaiting approval from @hiero-ledger/hiero-enterprise-java-committers and @hiero-ledger/hiero-enterprise-java-maintainers.