docs (SECURITY): Fix image syntax again

Example was using indirection, but outer square brackets are needed to
make the image the content of the link

SECURITY.md

@@ -17,7 +17,7 @@ in older versions.
 
 Please use the button below.
 
-### ![https://img.shields.io/badge/Report_a_vulnerability-00cc00](https://github.com/make-all/tuya-local/security/advisories/new)
+### [![Report a vulnerability](https://img.shields.io/badge/Report_a_vulnerability-00cc00)](https://github.com/make-all/tuya-local/security/advisories/new)
 
 This will give the developers a heads up about the issue before posting publicly, to protect other users who may be affected.
 Security issues will be treated as top priority, so you should get a response within 72 hours, usually much sooner.