Adding root to docker run

[germa89]

Because in https://github.com/pyansys/mapdl-docker-image-builder/pull/30 the root stopped to be the default user.

We need the root to operate at /jobs. Otherwise the CICD shows:

Digest: sha256:3082a8d05bc4c0cd0e4a7e978be14c86f7cafd381ff0b556d097285a5db147a0
Status: Downloaded newer image for ghcr.io/pyansys/mapdl:v22.2-ubuntu
ghcr.io/pyansys/mapdl:v22.2-ubuntu
mkdir: cannot create directory '/jobs': Permission denied
Error: Process completed with exit code 1.

Also when using the docker image as a container for running the test locally we see the following error in the checkout action:

Run actions/checkout@v3
/usr/bin/docker exec  76ecd63f3a8f7a867b0adef45933ee0e317478b8c8b47cf18b0a8dcbec98db83 sh -c "cat /etc/*release | grep ^ID"
##[debug]ID=ubuntu
##[debug]ID_LIKE=debian
##[debug]Running JavaScript Action with default external tool: node16
node:internal/fs/utils:344
    throw err;
    ^

Error: EACCES: permission denied, open '/__w/_temp/_runner_file_commands/save_state_07907405-b62e-4cec-86f4-a6f9bb258ed2'
    at Object.openSync (node:fs:585:3)
    at Object.writeFileSync (node:fs:21[53](https://github.com/pyansys/pymapdl/actions/runs/3694418976/jobs/6255654262#step:3:54):35)
    at Object.appendFileSync (node:fs:2215:6)
    at Object.issueFileCommand (/__w/_actions/actions/checkout/v3/dist/index.js:2344:8)
    at Object.saveState (/__w/_actions/actions/checkout/v3/dist/index.js:11928:31)
    at Object.153 (/__w/_actions/actions/checkout/v3/dist/index.js:4095:10)
    at __webpack_require__ (/__w/_actions/actions/checkout/v3/dist/index.js:22:30)
    at Object.287 (/__w/_actions/actions/checkout/v3/dist/index.js:7064:34)
    at __webpack_require__ (/__w/_actions/actions/checkout/v3/dist/index.js:22:30)
    at Object.853 (/__w/_actions/actions/checkout/v3/dist/index.js:31838:36) {
  errno: -13,
  syscall: 'open',
  code: 'EACCES',
  path: '/__w/_temp/_runner_file_commands/save_state_07907405-b62e-4cec-86f4-a6f9bb2[58](https://github.com/pyansys/pymapdl/actions/runs/3694418976/jobs/6255654262#step:3:59)ed2'
}
##[debug]Node Action run completed with exit code 1
##[debug]Finishing: Install Git and checkout project

[github-actions]

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• BUG
• NEW FEATURE
• Enhancement
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[codecov]

Codecov Report

Merging #1693 (09e192b) into main (a0471db) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1693      +/-   ##
==========================================
+ Coverage   85.20%   85.23%   +0.02%     
==========================================
  Files          45       45              
  Lines        7511     7511              
==========================================
+ Hits         6400     6402       +2     
+ Misses       1111     1109       -2     

[germa89]

Looking forward to get some feedback from @greschd about the root stuff. I would like to avoid to use -u=0:0 if possible so we only execute certain commands as root, not the whole workflow.

[germa89]

Merging from now, because I need to keep working on other PRs.