Fix Semgrep schema doc

[hanzo]

Summary

Small followup to #1368, noticed that the schema doc is not being rendered correctly:

I'm not sure how to test that it will render correctly after this change, but this format matches the existing format used by the github schema:

cartography/docs/root/modules/github/schema.md

Lines 210 to 218 in f11d7b2

	#### Relationships
	- Software on Github repos can import Python libraries by optionally specifying a version number.
	```
	(GitHubRepository)-[:REQUIRES{specifier}]->(PythonLibrary)
	```
	- specifier: A string describing this library's version e.g. "<4.0,>=3.0" or "==1.0.2". This field is only present on the `:REQUIRES` edge if the repo's requirements file provided a version pin.