HHH-19591: Refactor verifyMeterNotFoundException to use assertThrows

[aliJavaTar]

Refactored the verifyMeterNotFoundException method in MicrometerStatisticsTest to use assertThrows instead of a try-catch block.

This improves readability and aligns with modern JUnit testing best practices.

Before:

try {
    registry.get(name).meter();
    Assert.fail(name + " should not have been found");
}
catch (MeterNotFoundException mnfe) {
}

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### ✅ Final Code: New `verifyMeterNotFoundException`

You already wrote it correctly! Here's the cleaned-up version for clarity:

```java
void verifyMeterNotFoundException(String name) {
    MeterNotFoundException exception = assertThrows(
        MeterNotFoundException.class,
        () -> registry.get(name).meter(),
        name + " should not have been found"
    );
    assertTrue(exception.getMessage().contains(name));
}

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https://hibernate.atlassian.net/browse/HHH-19591