Add a "production" argument to the dev_server script

When this argument is passed, set the environment to "production".

dev_server.sh

@@ -1,4 +1,13 @@
 #!/usr/bin/env zsh
 # Eryn Wells <eryn@erynwells.me>
 
-hugo server --buildDrafts --buildFuture --noHTTPCache --enableGitInfo
+if [[ "$1" == "production" ]]; then
+    hugo server \
+        --buildDrafts \
+        --buildFuture \
+        --noHTTPCache \
+        --enableGitInfo \
+        --environment production
+else
+    hugo server --buildDrafts --buildFuture --noHTTPCache --enableGitInfo
+fi