Bug 29761: Prevent batch patron modification to process several time the same patron

Bug 29761: Prevent batch patron modification to process several time the same patron

If a cardnumber, SMS number, or borrower number is inputted multiple times then the batch patron
modification page should not display that patron multiple times.

Test plan:
1. Create three text files that list card numbers, SMS numbers, and borrower numbers for three patrons. Example lists are below, notice in each there is one number duplicated:

Card numbers:
  23529000035676
  23529000651225
  23529000080862
  23529000035676

Borrower numbers:
  19
  49
  7
  49

SMS numbers:
  2125551212
  2125551212
  2125551213
  2125551214

2. Enable sending of SMS messages:
* Set SMSSendDriver system preference to Email

3. Make sure the cardnumbers, borrower numbers, and SMS numbers listed
above belong to patrons in your Koha

4. Go to Tools > Batch patron modification

5. Upload lists of cardnumbers, SMS numbers, and borrower numbers above, and confirm the following is happening in the batch patron modification page:
- Upload the text file of cardnumbers. Notice one patron is displayed twice
- Paste in the list of cardnumbers. Notice one patron is displayed twice
- Upload the text file of SMS numbers. Notice one patron is displayed twice
- Paste in the list of SMS numbers. Notice one patron is displayed twice
- Upload the text file of borrower numbers. Notice one patron is displayed twice
- Paste in the list of borrower numbers. Notice one patron is displayed twice

6. Apply patch and restart services

7. Repeat step 5 and this time observe that the patron record is not duplicated in the batch patron modification page

Sponsored-By: Catalyst IT
Signed-off-by: David Nind <david@davidnind.com>
JD Amended patch: adjust commit title
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>