Cleaner CI conda env setup | Selective weekly dependabot updates

[abejgonzalez]

• CI now uses the build-setup script to setup the env (allows the CI to use the conda-lock version given in the repo). This requires adding two new args to the script s.t. it can use a global conda env name and a github token.
• Adds the bartender token to the CIRCT update script in hopes of making it run CI automatically (this needs to be checked)
• Updates dependabot s.t. it only updates certain repos. Additionally, it updates everything on a weekly cadence instead of daily to reduce spam (I'll probably change the CIRCT update to weekly as well once it's confirmed to work w/ CI).

Related PRs / Issues:

Type of change:

• Bug fix
• New feature
• Other enhancement

Impact:

• RTL change
• Software change (RISC-V software)
• Build system change
• Other

Contributor Checklist:

• Did you set main as the base branch?
• Is this PR's title suitable for inclusion in the changelog and have you added a changelog:<topic> label?
• Did you state the type-of-change/impact?
• Did you delete any extraneous prints/debugging code?
• Did you mark the PR with a changelog: label?
• (If applicable) Did you update the conda .conda-lock.yml file if you updated the conda requirements file?
• (If applicable) Did you add documentation for the feature?
• (If applicable) Did you add a test demonstrating the PR?

• (If applicable) Did you mark the PR as Please Backport?