Merge pull request #2686 from nemesis/add-a-missing-backtick

Added a mising backtick in xcconfig_integrator warning message

lib/cocoapods/installer/user_project_integrator/target_integrator/xcconfig_integrator.rb

@@ -92,7 +92,7 @@ module Pod
               'project because your project already has a custom ' \
               'config set. In order for CocoaPods integration to work at ' \
               'all, please either set the base configurations of the target ' \
-              "#{target.name}` to `#{path}` or include the `#{path}` in your " \
+              "`#{target.name}` to `#{path}` or include the `#{path}` in your " \
               'build configuration.'
               false
             elsif !file_ref