pgAdmin 4 commit: [Authentication] Some of the base class functions are

[Authentication] Some of the base class functions are not static
function, but - methods. Hence - 'self' should be used, and not 'cls'.

Also - use a constant for duplicate string literal in LDAP
authentication implementation.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=414e3368529071a30e3ce96811edb9c58325ad74

Modified Files
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web/pgadmin/authenticate/internal.py |  6 +++---
web/pgadmin/authenticate/ldap.py     | 27 +++++++++++++++------------
2 files changed, 18 insertions(+), 15 deletions(-)