Remove Makefile from all intree extensions (#1312)

* Remove Makefile from all intree extensions

- Makefiles are not really common (rightly so) in JS projects and script
  entries in the package.json are good enough and what they're there
  for.

- Move to using yarn for installing dependencies and running scripts as
  that is what we mostly use for the rest of the project.

- Move from using make syntax to a dedicated script for building and
  testing extensions.

- add jest as extension devDep, go back to using makefile foreach syntax

- add correct exit code

- add yarn check call to install-deps

- add yarn invokation to find deps

Signed-off-by: Sebastian Malton <sebastian@malton.name>

Makefile

@@ -15,7 +15,8 @@ download-bins:
 	yarn download-bins
 
 install-deps:
-	yarn install --frozen-lockfile
+	yarn install --frozen-lockfile --verbose
+	yarn check --verify-tree --integrity
 
 compile-dev:
 	yarn compile:main --cache
@@ -56,10 +57,10 @@ else
 endif
 
 build-extensions:
-	$(foreach dir, $(wildcard $(EXTENSIONS_DIR)/*), $(MAKE) -C $(dir) build || exit $?; )
+	$(foreach dir, $(wildcard $(EXTENSIONS_DIR)/*), (cd $(dir) && npm install && npm run build || exit $?);)
 
 test-extensions:
-	$(foreach dir, $(wildcard $(EXTENSIONS_DIR)/*), $(MAKE) -C $(dir) test || exit $?; )
+	$(foreach dir, $(wildcard $(EXTENSIONS_DIR)/*), (cd $(dir) && npm install --dev && npm run test || exit $?);)
 
 build-npm: build-extension-types
 	yarn npm:fix-package-version