feat: extract node version from .nvmrc

this way the RUNTIME docker image always uses the same version as specified in the project

next-kubernetes.yml

@@ -12,12 +12,18 @@ include:
   
   EOF
     fi
-      
+    
+    if [ ! -f .nvmrc ]; then 
+      NODE_VERSION=14
+    else
+      NODE_VERSION="$(cat .nvmrc| sed '/^$/d' | sed 's/[a-z-]//g')"
+    fi
+    
     if [ ! -f Dockerfile ]; then
       echo "Creating Dockerfile"
       
       cat > Dockerfile <<EOF
-  FROM node:14-alpine
+  FROM node:$NODE_VERSION-alpine
   WORKDIR /app
   RUN apk add --no-cache git
   COPY --chown=node:node package.json yarn.lock ./