Update example nginx config for diagram

docs/example.nginx.conf

@@ -161,6 +161,11 @@ server {
     # We've applied other sandboxing techniques to mitigate the risk of running WebAssembly in this privileged scope
     if ($uri ~ ^\/unsafeiframe\/inner\.html.*$) { set $unsafe 1; }
 
+    # draw.io uses inline script tags in it's index.html. The hashes are added here.
+    if ($uri ~ ^\/bower_components\/drawio\/src\/main\/webapp\/index.html.*$) {
+        set $scriptSrc "'self' 'sha256-6zAB96lsBZREqf0sT44BhH1T69sm7HrN34rpMOcWbNo=' 'sha256-6g514VrT/cZFZltSaKxIVNFF46+MFaTSDTPB8WfYK+c=' resource: https://${main_domain}";
+    }
+
     # privileged contexts allow a few more rights than unprivileged contexts, though limits are still applied
     if ($unsafe) {
         set $scriptSrc "'self' 'unsafe-eval' 'unsafe-inline' resource: https://${main_domain}";