Add tests for nginx.conf directives (#1)

Adds tests to make sure all the `nginx.conf` directives (the redirects and rewrites and such) are all correct.

- Uses the `busted` framework
- The tests are run in a Docker container by the bash script `test.sh`
- Self-signed certs are generated in `Dockerfile` for all the domain names
- Adds new `Makefile` commands: `test`, `image-build` and `image-rm`

Reviewed-on: #1
Co-authored-by: Catalin Mititiuc <webdevcat@proton.me>
Co-committed-by: Catalin Mititiuc <webdevcat@proton.me>

Dockerfile

@@ -1,4 +1,4 @@
-FROM openresty/openresty:1.27.1.2-0-bookworm-buildpack
+FROM openresty/openresty:bookworm-buildpack
 
 WORKDIR /opt/app
 
@@ -11,7 +11,27 @@ RUN apt-get update && apt-get install -y \
         wget -q -O $pkgname $pkgurl && dpkg -i $pkgname && rm $pkgname
 
 RUN luarocks install sitegen
-RUN luarocks install busted
+
+# needed for sitegen watcher
 RUN luarocks install inotify INOTIFY_INCDIR=/usr/include/x86_64-linux-gnu/
 
+# needed for testing
+RUN luarocks install busted
+RUN luarocks install luajit-curl
+RUN luarocks install luasocket # needed for testing nginx reverse proxy
+
+RUN mkdir -p /var/www/certs/miti.sh \
+    && openssl req -x509 -newkey rsa:4096 -nodes \
+      -keyout /var/www/certs/miti.sh/privkey.pem \
+      -out /var/www/certs/miti.sh/fullchain.pem \
+      -sha256 -days 365 -subj '/CN=miti.sh' \
+      -addext "subjectAltName=DNS:miti.sh,DNS:git.miti.sh,DNS:apps.miti.sh"
+
+RUN mkdir -p /var/www/certs/webdevcat.me \
+    && openssl req -x509 -newkey rsa:4096 -nodes \
+      -keyout /var/www/certs/webdevcat.me/privkey.pem \
+      -out /var/www/certs/webdevcat.me/fullchain.pem \
+      -sha256 -days 365 -subj '/CN=webdevcat.me' \
+      -addext "subjectAltName=DNS:webdevcat.me,DNS:git.webdevcat.me,DNS:apps.webdevcat.me"
+
 CMD ["sh", "-c", "openresty -p `pwd` -g 'daemon off;'"]