fixed default formatter negative epoch milli errors

[kbharathy]

Description

Negative epoch millis with certain length, results with parsing exception for fields using default format ("strict_date_optional_time||epoch_millis").

negative values(-561600000, -5616000000) are parsed incorrectly with default format "strict_date_optional_time||epoch_millis".
with error message,
java.lang.ArithmeticException: long overflow

negative values(-2177434800) are parsed incorrectly with default format "strict_date_optional_time||epoch_millis"
with error message,
java.time.DateTimeException: Invalid value for Year (valid values -999999999 - 999999999): -2177434800

Fixed by reducing length from 10 to 4 - Helped to parse values correctly now.

Related Issues

Resolves #16979

Check List

• Functionality includes testing.
• API changes companion pull request created, if applicable.
• Public documentation issue/PR created, if applicable.

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[github-actions]

❌ Gradle check result for 0272e31: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[kbharathy]

Closing this PR now, need to fix related test failures.