Upgrade gittools

[tobiasdiez]

This should fix the problem with the missing third version specifier. GitTools/GitVersion#1994 is fixed in 5.3.3

• Change in CHANGELOG.md described (if applicable)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked documentation: Is the information available and up to date? If not created an issue at https://github.com/JabRef/user-documentation/issues or, even better, submitted a pull request to the documentation repository.

[koppor]

Unsure why our depend a bot did not update that... --> https://github.com/JabRef/jabref/blob/master/.github/workflows/automerge.yml

[tobiasdiez]

Because that's not supported by dependabot. It only updates actions themselves, but not tools referenced in these actions (it's the same with the jdk, node version, ....)