chore: update npm scripts and synth.py (#721)

Update npm scripts: add clean, prelint, prefix; make sure that lint and fix are set properly. Use post-process feature of synthtool.

Author: alexander-fenster

handwritten/bigtable/package.json

@@ -40,7 +40,9 @@
     "presystem-test": "npm run compile",
     "system-test": "mocha build/system-test --timeout 600000",
     "pretest": "npm run compile",
-    "test": "c8 mocha build/test"
+    "test": "c8 mocha build/test",
+    "clean": "gts clean",
+    "precompile": "gts clean"
   },
   "dependencies": {
     "@google-cloud/paginator": "^3.0.0",

handwritten/bigtable/synth.py

@@ -1,7 +1,7 @@
 import synthtool as s
 import synthtool.gcp as gcp
+import synthtool.languages.node as node
 import logging
-import subprocess
 import os
 
 logging.basicConfig(level=logging.DEBUG)
@@ -56,6 +56,4 @@
 )
 s.copy(templates)
 
-subprocess.run(['npm', 'install'])
-subprocess.run(['npm', 'run', 'fix'])
-subprocess.run(['npx', 'compileProtos', 'src'])
+node.postprocess_gapic_library()