Separate docs build workflow

[purva-thakre]

Description

As discussed during the community call today, this PR splits the docs build job into a separate workflow. This makes it easier for us to rerun pytest related jobs without waiting for the docs build to be completed.

After this PR is merged, #2437 will be rebased.

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License

• I license this contribution under the terms of the GNU GPL, version 3 and grant Unitary Fund the right to provide additional permissions as described in section 7 of the GNU GPL, version 3.

Before opening the PR, please ensure you have completed the following where appropriate.

• I added unit tests for new code.
• I used type hints in function signatures.
• I used Google-style docstrings for functions.
• I updated the documentation where relevant.
• Added myself / the copyright holder to the AUTHORS file

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.70%. Comparing base (e61c058) to head (a124cb0).
Report is 45 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2441   +/-   ##
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  Coverage   98.70%   98.70%           
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  Files          88       88           
  Lines        4083     4083           
=======================================
  Hits         4030     4030           
  Misses         53       53           

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[purva-thakre]

Pinging @natestemen because I want to rerun the jobs in #2447 without waiting for the docs build.

Once this PR is merged, I could rebase the other branch.

[natestemen]

I don't see any problems with this. We'll see how it goes, and can revert if any problems arise.

[natestemen]

IIRC this should do the same thing. Can you double check? Maybe in the past it was a different command, but now I think make install xyz performs the same action as make install.

Suggested change

	make install requirements
	make install

[purva-thakre]

I do not know how a makefile works that well. It's on my list of todos.

Maybe in the past it was a different command,

Looking through the targets, why were we using make install requirements in the past? According to this, make install will install from the first installation target which is install. I see development is utilized in setup.py where we install things listed in requirements/.

mitiq/Makefile

Lines 49 to 51 in 231319d

	.PHONY: install
	install:
	pip install -e .[development]

mitiq/Makefile

Lines 59 to 61 in 231319d

	.PHONY: requirements
	requirements: requirements/requirements.txt
	pip install -r requirements/requirements.txt

Why do we have two separate installation targets in the makefile? IMO both appear to behave the same unless I am missing something.

[natestemen]

pip install -e .[development]

This will install

1. an editable installation of Mitiq (-e is short for --editable)
2. all the dependencies (the [development] "tag" is defined in setup.py here to mean all of the dependencies found in requirements/.)

pip install -r requirements/requirements.txt

This will only install the requirements listed in requirements/requirements.txt which is currently numpy, scipy, cirq-core, and tabulate. I can't find any uses of this command in Mitiq and it should be safe to remove. I've added a note for the community call this week to discuss.

[cosenal]

Discussed in the community call. Green light from everyone on removing it.
@purva-thakre is going to create a PR to remove it (no need for a ticket, we can just refer to this discussion) and there we will make sure all the builds pass.

[purva-thakre]

Going to go ahead and merge this if docs passes as one failure is what's in #2431