Extend libssl,unwind,notify to full 2019 range (game-ci#93)

Fix build process for 2018.2 and below (game-ci#87)

Tested locally, merging

Bump actions/cache from v2 to v2.1.4 (game-ci#73)

Bumps [actions/cache](https://github.com/actions/cache) from v2 to v2.1.4.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](actions/cache@v2...26968a0)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Set locale to C.UTF-8 in Dockerfile (game-ci#58)

Install Git LFS (game-ci#47)

* Install Git LFS

* Moved git lfs install before apt-get clean

cats (game-ci#45)

* cats

* try event_type

* only when opened

* and reopened

Add git and git-lfs (game-ci#41)

Added libglu (game-ci#37)

This will solve "error-while-loading-shared-libraries-libglu-so-1" message while running unity-editor.

Merge pull request game-ci#34 from Unity-CI/bugfix/fix-dockerfile-con…

…dition

Fix condition by replacing [[ with [ closes game-ci#33

Prevent any caching between repo versions