Decentralized Devstack changes: Add and push Dockerfile; add decentralized devstack settings (#24666)

* Add and push Dockerfile; add decentralized devstack settings

Co-Authored-By: Diana Huang <dkh@edx.org>
Co-Authored-By: Kyle McCormick <kmccormick@edx.org>

* Remove Python requirements hack

Remove the attempted optimization to the installation of Python
package dependencies.  The dependencies in edx-platform change
about three times per day, so this was of dubious value.  And
because npm is run through nodeenv, which is a Python package,
the Python dependencies installation has to happen first.

* ARCHBOM-1439: Changing workdir to /edx/app/edxapp/edx-platform (#24835)

Context: The Dockerfile tries to stay in sych with legacy stuff.
In the ansible we configure the directory structure such that things
relating to the app but not in the codebase,
such as the env file wind up in /edx/app/edxapp/.
And the codebase winds up in /edx/app/edxapp/edx-platform.

I think due to accident, the...

* Add Dockerfile.
* Add gunicorn config files for local development.
* Add .dockerignore file.

Co-authored-by: Joseph Mulloy <jmulloy@edx.org>
Co-authored-by: Fred Smith <derf@edx.org>
Co-authored-by: Adam Blackwell <ablackwell@edx.org>
Co-authored-by: Kyle McCormick <kmccormick@edx.org>
Co-authored-by: Nadeem Shahzad <nshahzad@edx.org>

Update ORA to 2.6.16 | Fixes the text_response property to be more backwards-compatible with _old_ ORA blocks.

This reverts commit 0c8d66bb.

We needed those files for the push translation
jenkins job as job has been updated to run
without commiting any changes to reo. we no
longer need those files in repo.

translations to transifex. This will help edx-platform
automated jenkins translation job understand when to push
translations to transifex.

LEARNER-1860

FEDX-121

The previous approach for handling NPM assets was
to symlink them into the static directory. This appeared
to cause trouble with the asset pipeline where the files
in question were not installed and then old versions were
picked up instead.

This change instead copies NPM libraries to a new
static directory so that the pipeline can consume them
as with any other file. This new directory is added to
.gitignore so that the files don't get accidentally
checked in.

Sass compilation is no longer dependent on Ruby, so we are
removing its dependencies.

This is a squash of 38 commits ending with
5b080f979d692804452400ac5bed9b17c50b001e