ci: stop the persistence RSS check rebuilding the workspace

`check-persistence-backlog-budget.py` runs its measurement through
`cargo test -p codewhale-tui --lib` with default features, but the step
before it on the same runner is
`cargo nextest run --workspace --all-features --locked`. This crate's
`--all-features` adds `web` and `long-running-tests` on top of the default
`tui,json,toml`, so the two are a different feature unification and Cargo
rebuilds the crate and everything downstream of it rather than reusing what
was just compiled.

It is the second-largest step in the macOS leg: 10 minutes of a 71-minute
job, for a test that runs in well under a second. Measured locally, the same
command against a warm tree of the *other* feature set takes 9.5s when the
features match and 132s when they do not — the delta is entirely the rebuild.

Aligning the flag makes the measurement reuse the nextest artifacts. The
measured test is unchanged and still runs `--exact --ignored
--test-threads=1`, which is what the receipt's determinism depends on.

scripts/measure-persistence-backlog.py

@@ -33,6 +33,13 @@ def measurement_command() -> list[str]:
         "cargo",
         "test",
         "--locked",
+        # Match the feature set CI's `cargo nextest run --workspace
+        # --all-features` already built. Default features are a *different*
+        # unification (this crate's `--all-features` adds `web` and
+        # `long-running-tests`), so asking for them here rebuilt the crate and
+        # its dependents from scratch — ten minutes of the macOS leg spent
+        # recompiling artifacts the previous step had already produced.
+        "--all-features",
         "-p",
         "codewhale-tui",
         "--lib",