Fix obsolete Secure Release Process links

Why is this change being made?

As I was trying to figure out how to release a new project under security-products I found the Secure Release Process page under the handbook.

In !124000 (merged) it was deleted without redirects being put in place.

Before then it had been moved from /handbook/engineering/development/secure/release_process to /handbook/engineering/development/sec/secure/release_process in !102070 (merged) without adding a redirect for the old location.

Location	Broken Target Location
"more information" link inside the group description on https://gitlab.com/security-products	https://about.gitlab.com/handbook/engineering/development/secure/release_process.html#location-of-container-images
"release issue" link under https://about.gitlab.com/handbook/engineering/development/sec/secure/static-analysis/#week-1	https://about.gitlab.com/handbook/engineering/development/sec/secure/release_process.html
"established release process" link under https://about.gitlab.com/handbook/engineering/development/sec/secure/static-analysis/#go-security-fixes	https://about.gitlab.com/handbook/engineering/development/sec/secure/release_process.html#security-and-build-fixes-of-go
"Secure Release Process" link under https://about.gitlab.com/handbook/engineering/workflow/code-review/#project-maintainer-process-for-gitlab-secure-analyzers	https://about.gitlab.com/handbook/engineering/development/sec/secure/release_process.html

side note: I included some additional removals of https://about.gitlab.com/ for /handbook page references in the files I found with broken links since this

Author Checklist

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