Fixed a non deterministic test in StatementGeneratorTest

[yugvajani]

Description

This PR fixes the non deterministic test :

org.apache.iotdb.db.queryengine.plan.parser.StatementGeneratorTest.testCreateSchemaTemplate

This tests failed under NonDex tool as explained in the issue IOTDB-6352 .

Steps to Reproduce

To reproduce the problem, first build the module and then run the nondex command:

mvn install -pl iotdb-core/datanode -am -DskipTests

mvn -pl iotdb-core/datanode edu.illinois:nondex-maven-plugin:2.1.7:nondex -Dtest=org.apache.iotdb.db.queryengine.plan.parser.StatementGeneratorTest#testCreateSchemaTemplate

The reason for the flakiness of this test is due to non-deterministic order of the measurements returned by the function statement.getMeasurements(). Fixed the issue by comparing the measurements as Set instead of List as Set ensures a deterministic order.

Please let me know if you have any questions or need any additional justification/changes from my side.

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This PR has:

• been self-reviewed.
  • concurrent read
  • concurrent write
  • concurrent read and write
• added documentation for new or modified features or behaviors.
• added Javadocs for most classes and all non-trivial methods.
• added or updated version, license, or notice information
• added comments explaining the "why" and the intent of the code wherever would not be obvious
  for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold
  for code coverage.
• added integration tests.
• been tested in a test IoTDB cluster.

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Key changed/added classes (or packages if there are too many classes) in this PR