Issue templates: Remove duplicate links to security policy (#91590)

* Remove security link from config file
* Delete security.md

.github/ISSUE_TEMPLATE/config.yml

@@ -5,6 +5,3 @@ contact_links:
   - name: "Proposing new features"
     about: "Submit major feature proposal (e.g. syntax changes) to an ideas forum first."
     url: "https://discuss.python.org/c/ideas/6"
-  - name: "Reporting security vulnerabilities"
-    about: "See here for details on reporting security vulnerabilities in CPython"
-    url: "https://www.python.org/dev/security/"

.github/ISSUE_TEMPLATE/security.md

----
-name: Security vulnerability report
-about: Submit a report regarding a security vulnerability
-labels: "type-security"
----
-
-<!--
-  Note that security issues should generally first be sent to the "security at python dot org" email address.
-  See here for further details: https://www.python.org/dev/security/
--->
-
-**Security vulnerability report**
-
-A description of what the security vulnerability is.
-
-**Your environment**
-
-<!-- Include as many relevant details about your environment as possible -->
-
-- CPython versions tested on:
-- Operating system and architecture:
-
-<!--
-You can freely edit this text. Remove any lines you believe are unnecessary.
--->