Remove old build system

tests/functional/ca/local.mk

@@ -1,29 +0,0 @@
-ca-tests := \
-  $(d)/build-with-garbage-path.sh \
-  $(d)/build.sh \
-  $(d)/build-cache.sh \
-  $(d)/concurrent-builds.sh \
-  $(d)/derivation-json.sh \
-  $(d)/duplicate-realisation-in-closure.sh \
-  $(d)/eval-store.sh \
-  $(d)/gc.sh \
-  $(d)/import-from-derivation.sh \
-  $(d)/new-build-cmd.sh \
-  $(d)/nix-copy.sh \
-  $(d)/nix-run.sh \
-  $(d)/nix-shell.sh \
-  $(d)/post-hook.sh \
-  $(d)/recursive.sh \
-  $(d)/repl.sh \
-  $(d)/selfref-gc.sh \
-  $(d)/signatures.sh \
-  $(d)/substitute.sh \
-  $(d)/why-depends.sh
-
-install-tests-groups += ca
-
-clean-files += \
-  $(d)/config.nix
-
-test-deps += \
-  tests/functional/ca/config.nix