Chipyard 1.12.1

Fixes bug with Conda install flow. Adds pre-release of vector unit.

Added

• Add dependabot to auto-update submodules (by @abejgonzalez in #1940)
• Update dependabot to also update GH-A workflows (by @abejgonzalez in #1950)
• Nexys video fpga bringup config (by @SeahK in #1942)
• Integrate vector unit (by @jerryz123 in #1928)

Changed

• Remove need for users to install conda-lock themselves (by @abejgonzalez in #1941)
• Cleaner CI conda env setup | Selective weekly dependabot updates (by @abejgonzalez in #1957)

Fixed

• Fix VLSI CI - Fix conda environment creation (by @abejgonzalez in #1963)
• Create fresh conda environment for conda-lock instead of cloning base (by @abejgonzalez in #1970)

Removed

• Remove pre-commit (by @abejgonzalez in #1938)
• Delete .github/workflows/weekly-tag.yml (by @abejgonzalez in #1939)

Full Changelog: 1.12.0...main