Fix hak check for matrix-seshat

[t3chguy]

Should fix issues like https://github.com/element-hq/element-web/actions/runs/23893575431/job/69673067071?pr=33008

[richvdh]

For future reference/issue search, the error message was:

> node scripts/hak/index.ts

hak check: matrix-seshat
Error: spawn python ENOENT
    at Process.ChildProcess._handle.onexit (node:internal/child_process:286:19)
    at onErrorNT (node:internal/child_process:484:16)
    at processTicksAndRejections (node:internal/process/task_queues:90:21)

[richvdh]

Do we know what changed to necessitate this?

[t3chguy]

Something on github's parter images, seems like python is sometimes not symlinked to python3. It isn't consistent and hard to validate. Nowadays node-gyp seems to be able to use either python or python3 so checking for either tool should be the way to go.

[RiotRobot]

The backport to staging failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-staging staging
# Navigate to the new working tree
cd .worktrees/backport-staging
# Create a new branch
git switch --create backport-33030-to-staging
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 0a8ef85f2f8237aa67e866e7eba8985e47ff9b86
# Push it to GitHub
git push --set-upstream origin backport-33030-to-staging
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-staging

Then, create a pull request where the base branch is staging and the compare/head branch is backport-33030-to-staging.