Remove unused files under .github/workflows

[myl7]

CI of the project uses tunathu/thuthesis-test-env image, which is built according to .github/workflows/Dockerfile of tuna/thuthesis. Since the project does not include the Dockerfile, texlive.profile and install-texlive.sh in .github/workflows, which is used only in Docker building, is unused in the project. I would suggest to remove them to avoid confusing users.

[zepinglee]

Yes, you are right. The install-texlive.sh and texlive.profile files were originally used for installing a TeX distribution for every run of CI. It was then switched to the docker image because of some problems with CTAN and those files are no longer in valid use.

[zepinglee]

Fixed in 6e7abb1.