Merge pull request #12286 from cdrini/hotfix/http2

Re-enable http2

Author: mekarpeles

docker/covers_nginx.conf

@@ -32,6 +32,7 @@ upstream covers_backend {
 server {
       listen 80;
       listen 443;
+      http2 on;
       server_name  covers.openlibrary.org;
 
       root /openlibrary;

docker/web_nginx.conf

@@ -71,6 +71,7 @@ server {
 server {
     listen 80;
     listen 443;
+    http2 on;
     server_name  openlibrary.org;
 
     # Set the referrer policy so browsers send referrers to our own servers