Use fully qualified image names in Dockerfiles. Minor syntax fixes to ENV variables

Dockerfile

@@ -1,7 +1,7 @@
 # This image will be published as dspace/dspace-angular
 # See https://github.com/DSpace/dspace-angular/tree/main/docker for usage details
 
-FROM node:18-alpine
+FROM docker.io/node:18-alpine
 
 # Ensure Python and other build tools are available
 # These are needed to install some node modules, especially on linux/arm64
@@ -22,5 +22,5 @@ ENV NODE_OPTIONS="--max_old_space_size=4096"
 # Listen / accept connections from all IP addresses.
 # NOTE: At this time it is only possible to run Docker container in Production mode
 # if you have a public URL. See https://github.com/DSpace/dspace-angular/issues/1485
-ENV NODE_ENV development
+ENV NODE_ENV=development
 CMD npm run serve -- --host 0.0.0.0

Dockerfile.dist

@@ -4,7 +4,7 @@
 # Test build:
 # docker build -f Dockerfile.dist -t dspace/dspace-angular:latest-dist .
 
-FROM node:18-alpine AS build
+FROM docker.io/node:18-alpine AS build
 
 # Ensure Python and other build tools are available
 # These are needed to install some node modules, especially on linux/arm64
@@ -26,6 +26,6 @@ COPY --chown=node:node docker/dspace-ui.json /app/dspace-ui.json
 
 WORKDIR /app
 USER node
-ENV NODE_ENV production
+ENV NODE_ENV=production
 EXPOSE 4000
 CMD pm2-runtime start dspace-ui.json --json