fix(cli): pg-delta workspace mount

[7ttp]

TL;DR:

db push crashes with ENOENT reading the pg-delta CA cert on every push against a hosted/TLS target,
missing Docker mount

Prob

exportCatalog writes the CA bundle to <cwd>/supabase/.temp/pgdelta/ and points sslrootcert at /workspace/... inside the container, but never mounted cwd to /workspace like every other pg-delta call site does.
Container looks for a file that was never shared with it.

Sol:

(pragmatic fix)
adds the same cwd:/workspace bind the sibling functions in internal/db/diff/pgdelta.go already has. that's it..

Ref:

• towards db push: "failed to cache migrations catalog" — pg-delta can't read pgdelta-target-ca.crt inside edge-runtime (ENOENT at /workspace/...) #5921