Merge pull request #236 from hathitrust/dependabot/bundler/rexml-3.3.9

Bump rexml from 3.3.6 to 3.3.9

Author: moseshll

Gemfile.lock

@@ -294,8 +294,7 @@ GEM
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     regexp_parser (2.6.0)
-    rexml (3.3.6)
-      strscan
+    rexml (3.3.9)
     rubocop (1.35.1)
       json (~> 2.3)
       parallel (~> 1.10)
@@ -351,7 +350,6 @@ GEM
     standard (1.16.1)
       rubocop (= 1.35.1)
       rubocop-performance (= 1.14.3)
-    strscan (3.1.0)
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)
     thor (1.3.1)