Test nix build --json return output paths in floating CA case

Adding a test to ensure there is no regression.

The tests that are split out of `tests/build.sh` are ones that don't yet
work with CA derivation. I have not yet evaluated whether they should or
not.

This behavior, reported missing in issue #4661, already got fixed in
PR #4818, but didn't get a test case then.

tests/local.mk

@@ -21,6 +21,7 @@ nix_tests = \
   binary-cache.sh \
   multiple-outputs.sh \
   ca/build.sh \
+  ca/new-build-cmd.sh \
   nix-build.sh \
   gc-concurrent.sh \
   repair.sh \
@@ -103,6 +104,8 @@ nix_tests = \
   ssh-relay.sh \
   plugins.sh \
   build.sh \
+  build-delete.sh \
+  output-normalization.sh \
   ca/nix-run.sh \
   selfref-gc.sh ca/selfref-gc.sh \
   db-migration.sh \