Update for Ruby 3.0 (sds#741)

HarlemSquirrel · web-flow · commit 7312d5e4afa3 · 2021-02-12T09:34:46.000-08:00
rexml is no longer default gem in Ruby 3.0
diff --git a/.travis.yml b/.travis.yml
@@ -7,6 +7,7 @@ rvm:
   - 2.5
   - 2.6
   - 2.7
+  - 3.0
 
 before_script:
   - git config --global user.email "travis@travis.ci"
diff --git a/overcommit.gemspec b/overcommit.gemspec
@@ -29,4 +29,5 @@ Gem::Specification.new do |s|
 
   s.add_dependency          'childprocess', '>= 0.6.3', '< 5'
   s.add_dependency          'iniparse', '~> 1.4'
+  s.add_dependency          'rexml', '~> 3.2'
 end
