[new release] dkml-workflows (1.1.0)

CHANGES:

New Features:
- Desktop testing for macOS/Intel (or macOS/ARM64 with Rosetta emulator) and Linux 32/64-bit on Intel/AMD
- Help messages for desktop testing on Windows
- Optional secondary switch `two` in addition to primary switch `dkml` enabled with
input variable `SECONDARY_SWITCH=true`

Breaking changes:
- The GitLab job names `build_linux`, `build_macos` and `build_win32` are now private job names `.linux:setup-dkml`,
`.macos:setup-dkml` and `.win32:setup-dkml`. This means in your own `.gitlab-ci.yml` you will need an "extends" statement,
like so:
```yaml
build_linux:
extends: .linux:setup-dkml # ADD THIS ONE LINE!
script:
- opamrun exec -- echo Build me some Linux stuff
```

*Why break the API?*

This change was done so you could do incremental staged builds where job A does only the setup (which caches the OCaml
compiler) and where the second job B does both the setup and the full build of your OCaml code. By using a private job
name that starts with a dot (.) like `.linux:setup-dkml`, both job A and job B can extend from `.**OS**:setup-dkml` to
share the setting up of the OCaml compiler cache.

The benefit you get for the extra complexity is that you are more likely to stay under GitLab runner
time limits; the shared SaaS GitLab runners time out jobs at 2 hours.
For example Job A can take one hour or more for Windows when you enable `SECONDARY_SWITCH=true`.

Hypothetically you could do a full build of your code without the caching of the OCaml compiler that took 2.5 hours.
GitLab would fail your full build with time limit failures. But by splitting job A from job B, job A takes 1-1.5 hours
while job B would only take 1.5 hours plus a few minutes for reading the cache of job A. Now both job A and job B
can work without running into time limits.

*Why is it a minor break?*

Since there was no announcement of the previous 1.0.0 version, it is unlikely anyone is broken. And if
anyone is broken, they just need to add three `extends: .setup_dkml_XXX` to their script.

Other changes:
- Performance: Linux CI now avoids ~10 second ManyLinux (dockcross) unnecessary recursive chown of root:root
owned container files. As long as calling user is root (which is true for GitHub Actions and GitLab CI/CD)
the chown operation is skipped.
- Remove unused `gl_tags` matrix variable