fix: invalid API url

I misstyped the API URL T-T

comment_on_pr.sh

@@ -48,16 +48,12 @@ markdown_from_report() {
 		- `Name`: the name of the package/configuration.
 		- `Size`: the closure size (size on disk/NAR size + all transitive dependencies).
 		- `NAR Size`: the size of the build output (package without the dependencies).
+
+    </details>
 	EOF
   if [ "${2+set}" = "set" ]; then
     cat <<-"EOF"
 			- `[NAR] Size Change`: the amount changed compared to the main branch.
-
-      </details>
-		EOF
-  else
-    cat <<-"EOF"
-      </details>
 		EOF
   fi
   cat <<-"EOF"