No longer locks the Material unit tests job to a specific branch, but rather allows
locking to a specific commit from a given branch. This allows us to use the
"master" branch from the `components` repository.
PR Close#31569
Previously, the ivy-2019 branch of the Material (aka components) repo was
used, which contains some changes that were necessary to work with Ivy.
These changes are not longer necessary, as Material's master branch is
fully working with Ivy today. To be up-to-date with recent Material
development and its support for more recent dependencies, e.g. TypeScript,
it is desirable for us to be on a newer version of Material.
This commit moves the Material tests away from the ivy-2019 branch, to a
recent commit on master. We are not targeting the master branch itself,
as that would introduce a moving target into Angular's CI checks, which
is undesirable.
Lastly, the usage of gulp to run Material's tests is changed into using
Bazel, as Material itself is now also built with Bazel.
PR Close#31569
Paul Gschwendtner
JoostK