feat(gitlab): allow override gitAuthor

[viceice]

Changes:

Do not try to fetch gitAuthor if it's already user defined, renovate will ignore it anyways

Context:

This allows to use $CI_JOB_TOKEN to do yome dry run / run renovate withour PAT on gitlab.
https://gitlab.com/renovate-bot/renovate-runner/-/merge_requests/202

Documentation (please check one with an [x])

• I have updated the documentation, or
• No documentation update is required

How I've tested my work (please tick one)

I have verified these changes via:

• Code inspection only, or
• Newly added/modified unit tests, or
• No unit tests but ran on a real repository, or
• Both unit tests + ran on a real repository

[viceice]

renovate/lib/platform/index.ts

Lines 91 to 104 in d0434d5

	let gitAuthor: string;
	// istanbul ignore else
	if (config?.gitAuthor) {
	logger.debug(`Using configured gitAuthor (${config.gitAuthor})`);
	gitAuthor = config.gitAuthor;
	} else if (platformInfo?.gitAuthor) {
	logger.debug(`Using platform gitAuthor: ${String(platformInfo.gitAuthor)}`);
	gitAuthor = platformInfo.gitAuthor;
	} else {
	logger.debug(
	'Using default gitAuthor: Renovate Bot <renovate@whitesourcesoftware.com>'
	);
	gitAuthor = 'Renovate Bot <renovate@whitesourcesoftware.com>';
	}

[viceice]

ref #7273

[renovate-release]

🎉 This PR is included in version 26.6.0 🎉

The release is available on:

• GitHub release
• 26.6.0

Your semantic-release bot 📦🚀