fix(commitlint): Treat "Signed-off-by:" as a footer

Add a note keyword to the commitlint configuration that treats lines
starting with "Signed-off-by:" as footers. This prevents commitlint
errors if the line exceeds the max body length.

Signed-off-by: Martin Nonnenmacher <martin.nonnenmacher@bosch.io>

Author: mnonnenmacher

.commitlintrc.yml

@@ -6,7 +6,7 @@ parserPreset:
     headerPattern: '^(\w*)(?:\((.*)\))?!?: (.*)$'
     breakingHeaderPattern: '^(\w*)(?:\((.*)\))?!: (.*)$'
     headerCorrespondence: ['type', 'scope', 'subject']
-    noteKeywords: ['BREAKING CHANGE', 'BREAKING-CHANGE', '\[\d+\]:']
+    noteKeywords: ['BREAKING CHANGE', 'BREAKING-CHANGE', '\[\d+\]:', 'Signed-off-by:']
     revertPattern: '/^(?:Revert|revert:)\s"?([\s\S]+?)"?\s*This reverts commit (\w*)\./i'
     revertCorrespondence: ['header', 'hash']
 rules: