Add `identity` helper to tests.
Add `identity` helper to tests.

rlugojr/lodash,tonyonodi/lodash,boneskull/lodash,Xotic750/lodash,boneskull/lodash,tonyonodi/lodash,rlugojr/lodash,Xotic750/lodash,beaugunderson/lodash,msmorgan/lodash,steelsojka/lodash,msmorgan/lodash,steelsojka/lodash,Xotic750/lodash,beaugunderson/lodash