Fix environment-specific builds.

web/Makefile

@@ -1,11 +1,5 @@
 build:
-	pwd; \
-	. .env.${TARGET_ENV}; \
-	echo "Using API URL: ${VUE_APP_PM_API_BASE}"; \
-	npm run build
+	npm run build-${TARGET_ENV}
 
 serve:
-	VUE_APP_PM_API_BASE=/api \
-	VUE_APP_API_LOG_LEVEL=WARN \
-	VUE_APP_LOG_LEVEL=TRACE \
 	npm run serve