Only human readbale backup chars

[rullzer]

Fixes #14811
Only use humand readable chars (so no I and 1 etc)
Leaves 30^16 possibilities

Signed-off-by: Roeland Jago Douma roeland@famdouma.nl

[juliusknorr]

There was 1 failure:
133 |  
134 | 1) OCA\TwoFactorBackupCodes\Tests\Unit\Service\BackupCodeStorageTest::testCreateCodes
135 | Expectation failed for method name is equal to "generate" when invoked 5 time(s)
136 | Parameter 1 for invocation OCP\Security\ISecureRandom::generate(16, 'ABCDEFGHJKLMNPQRSTWXYZ23456789'): string does not match expected value.
137 | Failed asserting that two strings are equal.
138 | --- Expected
139 | +++ Actual
140 | @@ @@
141 | -'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'
142 | +'ABCDEFGHJKLMNPQRSTWXYZ23456789'
143 |  
144 | /drone/src/apps/twofactor_backupcodes/lib/Service/BackupCodeStorage.php:78
145 | /drone/src/apps/twofactor_backupcodes/tests/Unit/Service/BackupCodeStorageTest.php:90
146

[ChristophWurst]

There's also \OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE that includes lower case letters as well

[rullzer]

There's also \OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE that includes lower case letters as well

yeah lets just use that then ;)