fix(misc): Add rexml dependency (#3594)

* fix(misc): Add rexml dependency

Author: vincetran

build-support/Gemfile.lock

@@ -173,6 +173,7 @@ GEM
       uber (< 0.2.0)
     retriable (3.1.2)
     rexml (3.2.8)
+      strscan (>= 3.0.9)
     rouge (2.0.7)
     ruby2_keywords (0.0.5)
     rubyzip (2.3.2)
@@ -185,6 +186,7 @@ GEM
     simctl (1.6.8)
       CFPropertyList
       naturally
+    strscan (3.1.0)
     terminal-notifier (2.0.0)
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)