cache: add sudo as an option

[rockandska]

Describe the enhancement
Many people would like to cache some "system" directory but are not able to since it is the runner user who make the tar.
Adding a sudo option who could be used later by actions/cache will solve the problem

Code Snippet
There are many demands about it :
actions/cache#181 (comment)
actions/cache#133 (comment)
actions/cache#155
actions/cache#324 (comment)
actions/cache#629

[ssbarnea]

That is indeed a critical feature as downloading system packages can take a considerable amount of time.

[maciejskorski]

Upvote. My usecase is a scenario of UML support in Sphinx, which requires sudo apt-get install plantuml in addition to pip install.

[kennytrytek-wf]

Workaround:
As the first step in a job that needs root permissions to untar a cached object, grant tar root ownership and execution.

steps:
  - name: root suid tar
    run: sudo chown root:wheel /bin/tar && sudo chmod u+s /bin/tar

[benliao1]

Thanks for the suggestions @kennytrytek-wf this worked for me!

[notmgsk]

Workaround: As the first step in a job that needs root permissions to untar a cached object, grant tar root ownership and execution.

steps:
  - name: root suid tar
    run: sudo chown root:wheel /bin/tar && sudo chmod u+s /bin/tar

I got the error

 chown: invalid group: ‘root:wheel’

but this worked instead

    run: sudo chown root /bin/tar && sudo chmod u+s /bin/tar