refactor date parsing to use ISO_DATE_TIME

[maxbehr801]

No description provided.

[Copilot]

Pull request overview

This PR refactors date parsing in the CarbonReductorVariableMapper to use Java's built-in ISO_DATE_TIME formatter instead of a custom date pattern. The change simplifies the code and provides more flexibility in accepting ISO 8601 date-time formats with variable millisecond precision.

Changes:

• Replaced custom date pattern yyyy-MM-dd'T'HH:mm:ss.SSSX'['z']' with standard ISO_DATE_TIME formatter
• Simplified error message to remove specific format details
• Added parameterized test to verify parsing of ISO date-time strings with varying millisecond precision

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
CarbonReductorVariableMapper.java	Replaced custom date pattern with ISO_DATE_TIME formatter and simplified error message
CarbonReductorVariableMapperTest.java	Added parameterized test for variable-precision ISO date-time formats and updated error message assertion

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[Copilot]

The error message has been made less helpful by removing the expected format. While the old message included the specific expected format pattern, the new message provides no guidance to users on what format is expected. Consider adding information about the expected ISO 8601 format or providing an example in the error message to help users correct their input.

Suggested change

	throw new IllegalArgumentException("Milestone: Unknown date time format");
	throw new IllegalArgumentException("Milestone: Unknown date time format. Expected ISO 8601, e.g. '2024-01-31T13:45:00Z'.");

[lwluc]

Copilot findings are useful and should be resolved