GrumPHP not anchoring patterns, which yields false-positives

See:

https://github.com/indiehd/web-api/pull/151/files#diff-8d9043f013ef22f82e6536bdbbeb23e0R64

Basically, it seems that GrumPHP's pattern-matching mechanism does not anchor the patterns, so the filter string `dd()` would match both functions `dd()` and `add()`. That's problematic if true, and an Issue should be opened in the Grum repository accordingly.