installer: Clean up ext-dependency jQuery code
Follows-up
c8833d8e8ecc.
* Select the input elements by class to avoid accidentally trigging
on unrelated elements elsewhere on the page in the future, given
the generic selector.
* Use on('change') instead of deprecated change() alias.
* Set properties directly instead of via prop() indirection.
* Get attribute directly instead of via data() indirection.
Change-Id: I5158aa26b5fd7327d6795f0a31bbffbe99043fbf
(cherry picked from commit
fd8a4c707a9c053ccf20ba0594cfc9c11354a374)