Java Key Store files

JKS files contain potential secrets. Is there a way of configuring git-secrets to find JKS files? git-secrets appears to scan only file content. I'm not sure if JKS files have any distinguishing fixed content that can be scanned for to identify them.

Start by locating git-secrets' configuration and content-scanning entry points, then determine how binary JKS files could be identified. Done means the tool has a documented, testable way to detect JKS files rather than relying only on content scanning.

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