Sky130/Openroad Tutorial Fixes

[nayiri-k]

Many updates to Sky130/Openroad Hammer flow.
Improvements to Sky130 Commercial/Openroad tutorial documentation.
Switched to Sram22 SRAMs.

Remaining TO DOs (add as needed):

• update example-sky130.yml and example-designs files to eliminate redundant configs & have good floorplan/timing
• bump versions of hammer & hammer vendor plugins
• update changelog
• either add conda installs of packages required for VLSI tutorial to CI flow or to tutorial flow

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?

[harrisonliew]

In Chipyard's main README, can you add a link to the Hammer DAC paper like so:

H. Liew et al., DAC '22, pdf.

[abejgonzalez]

SFTM. Didn't read the main part of the tutorial in-depth.

[nayiri-k]

@abejgonzalez here is the VLSI tutorial flow, it currently passes CI but maybe it's a bit too hacky?