Squashed commit of the following:

commit e7a0e71
Author: Kareem Farid <[email protected]>
Date:   Sun Nov 3 13:22:53 2024 +0200

    lint

    Signed-off-by: Kareem Farid <[email protected]>

commit 9e25b72
Author: Kareem Farid <[email protected]>
Date:   Sun Nov 3 13:11:51 2024 +0200

    update changelog, Verilator.Lint, Yosys.JsonHeader

    Signed-off-by: Kareem Farid <[email protected]>

commit 36bca9b
Author: Kareem Farid <[email protected]>
Date:   Sun Nov 3 12:52:59 2024 +0200

    bugfix: allow unsetting variables in configuration files

    Signed-off-by: Kareem Farid <[email protected]>

commit b0246e6
Author: Kareem Farid <[email protected]>
Date:   Tue Oct 29 15:29:20 2024 +0300

    hotfix: incorrect error message when substiuting with a nonexistent step

commit 19109e1
Author: Mohamed Gaber <[email protected]>
Date:   Sat Oct 26 20:12:12 2024 +0300

    bugfix: odb steps dropping PYTHONPATH (#592)

    * `Odb.*`
      * Fixed OpenROAD dropping user-set `PYTHONPATH` values.

    ## Tool Updates

    * Use `NIX_PYTHONPATH` instead of `PYTHONPATH` in Docker and devshells
      to avoid collisions with user-set `PYTHONPATH` variables.

commit 627a5ab
Author: Mohamed Gaber <[email protected]>
Date:   Thu Oct 24 11:03:55 2024 +0300

    nix: make flake.createOpenLane shell more ergonomic

    ## Tool Updates
    * `flake.createOpenLaneShell` now gets OpenLane from `python3.pkgs`.
    * Fixed issue with `flake.createOpenLaneShell` where plugins would not get
      included due to an operator precedence issue.

commit 8451508
Author: Mohamed Gaber <[email protected]>
Date:   Thu Oct 24 10:57:58 2024 +0300

    hotfix: regression in nix/create-shell.nix

commit 1bfa43d
Author: Mohamed Gaber <[email protected]>
Date:   Mon Oct 21 21:05:05 2024 +0300

    Temporarily revert Colab's OpenLane version until it's fixed

Signed-off-by: Kareem Farid <[email protected]>