If you want to just change the threshold for showing the warning, use "git.inputValidationSubjectLength": <N>
for the subject line (the first line) and "git.inputValidationLength": <N>
for subsequent lines.
If you want to turn the validation off entirely, use "git.inputValidation": "off"
.
Put these settings in your settings.json file.
The worst that can happen if you have long subject lines for your commit messages is that it will be hard for you and others to quickly know what a commit has changed. Nothing will explode, but you'll probably thank yourself in the future if you make an effort to be concise. See also: Git Commit Messages: 50/72 Formatting.
See also the git docs on the commit command:
Though not required, it’s a good idea to begin the commit message with a single short (less than 50 character) line summarizing the change, followed by a blank line and then a more thorough description. The text up to the first blank line in a commit message is treated as the commit title, and that title is used throughout Git.