Remove use of conda from CI

[gnikit]

There is no reason or benefit using Anaconda instead of the
default Python Actions venvs for fprettify. This PR removes
Anaconda from the CI, drops testing on Python 3.6, adds Python 3.11 testing and adds dependabot alerts for Actions and PyPi.

Depends on #131 for README formatting
Depends on #135 for pyproject.toml, setup.cfg, etc.

[gnikit]

Not sure what you think of this @awvwgk, but I don't a compelling reason to use Anaconda over bare-bones Python

[nbehrnd]

Not sure what you think of this @awvwgk, but I don't a compelling reason to use Anaconda over bare-bones Python

@gnikit There might be reasons in other packages than fprettify to use Anaconda/Miniconda (and there is a separate repository of fprettify for conda[1]). This aside and in support of your argument to use "bare-bones Python" instead of Anaconda, I would add + those with interest in Fortran likely already have standard (C)Python intentionally installed, or use an operating system shipping by default with its standard library (e.g., Debian, Ubuntu family). So there is only the one-time installation of pip itself, and its later use to get fprettify from from PyPi. + With 3GB (Anaconda) and 400 MB (Miniconda),[1] their default addition to a system probably is /considerably/ larger than the of standard Python. On the other hand, I don't recall that the two former interact with fprettify significantly better (as in more reliable, or faster) than standard Python already does. [1] https://github.com/conda-forge/fprettify-feedstock [2] https://conda.io/projects/conda/en/latest/user-guide/install/index.html

[gnikit]

This change does not affect the conda-forge feedstock, it simply changes how we setup the CI. The conda-forge package will continue to work as expected.