Lock firebase-tools to 11.30.0

Node 14 not supported for firebase-tools 12

Author: thenav56

firebase/Dockerfile

@@ -1,6 +1,6 @@
 FROM node:14.18.0-alpine
 RUN npm install firebase-functions@latest firebase-admin@latest --save
-RUN npm install -g firebase-tools
+RUN npm install -g firebase-tools@11.30.0
 COPY . /firebase
 RUN cd firebase/functions && npm install
 WORKDIR /firebase/