Bug 32221: Borrowers.password should no longer be an option

Bug 32221: Borrowers.password should no longer be an option

When creating a notice template the user has the option to add the borrower's
password to the template. This should be removed as the password should not be
an option to be added to a notice.

Test plan:
1) Navigate to Tools > Notices and slips
2) Either create a new notice or edit an existing notice
3) Observe that in the list of fields available to insert into the message body,
   there is the option for "borrowers.password"
4) Apply patch
5) Navigate to the same menu
6) Observe that the "borrowers.password" option is now no longer visible

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 9608b16a6ba9d877dddc75beb1e1eef691f7b21a)
Signed-off-by: Matt Blenkinsop <matt.blenkinsop@ptfs-europe.com>
(cherry picked from commit 7a143c19ad570adf8ab6cdf6f65a5456f7357ad3)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
(cherry picked from commit 2a81c5d8cc7e0ced742cf5f1fb99b5df62b1bc01)
Signed-off-by: Arthur Suzuki <arthur.suzuki@biblibre.com>