CAMEL-19551: camel-jpa ensure tests have assertions

[gbhavya07]

Description

Adds explicit assertions for startup operations in camel-jpa tests.

Several tests invoked consumer.start() or context.start() without directly asserting successful execution. This change wraps those operations with assertDoesNotThrow, making the expected startup behavior explicit and improving test clarity.

Updated tests:

• AbstractJpaMethodTest
• JpaTest
• JpaWithNamedQueryTest
• JpaWithNamedQueryAndParametersTest
• JpaIdempotentConsumerTest

This is a test-only change and does not modify component behavior.

Validation:

• Ran ./mvnw -pl components/camel-jpa -DskipITs test
• Tests run: 96
• Failures: 0
• Errors: 0

Target

• I checked that the commit is targeting the correct branch (Camel 4 uses the main branch)

Tracking

• JIRA issue: CAMEL-19551

Apache Camel coding standards and style

• I checked that each commit in the pull request has a meaningful subject line and body.

• I ran the relevant module tests locally and verified they pass.

[apupier]

all the modified tests already have assertions. I'm not sure it is adding a lot of clarity in these cases.