The hash-pinned requirements-semgrep.txt kept breaking: Semgrep pins its
own dependencies to exact or compatible-release versions, so Dependabot
bumps of any of them (importlib-metadata, exceptiongroup, jsonschema,
peewee, wcmatch, wrapt, ...) made the job fail with ResolutionImpossible.
Install the latest Semgrep with pip instead, remove the lock file and the
Dependabot ignore list that tried to work around it.
Signed-off-by: Niels Lohmann <mail@nlohmann.me>