Update dated/broken links in the docs

[PeterDaveHello]

Sorry that I don't really understand the meaning of some checks in the list so I didn't mark them checked.

• Your contribution is written in the 2nd person (e.g. you)
• Your contribution is written in an active present form for as much as possible.
• You have made sure that the reference section is up to date (e.g. please add sources you have used, make sure that the references to MITRE/MASVS/etc. are up to date)
• Your contribution has proper formatted markdown and/or code
• Any references to website have been formatted as [TEXT](URL “NAME”)
• You verified/tested the effectiveness of your contribution (e.g.: is the code really an effective remediation? Please verify it works!)

[cpholguera]

Thanks for the help @PeterDaveHello!