pgAdmin 4 commit: Set proper focus on tab navigation for file manager d

Set proper focus on tab navigation for file manager dialog. Fixes #5107
 - Show focus when the Tab key is pressed
 - Pressing the Enter key on C:\ drive does not open it on Windows

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=c9500a51228f386565e2897d96314fa675d43331
Author: Murtuza Zabuawala <murtuza.zabuawala@enterprisedb.com>

Modified Files
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docs/en_US/release_notes.rst                         |  1 +
docs/en_US/release_notes_4_19.rst                    | 20 ++++++++++++++++++++
web/pgadmin/misc/file_manager/static/js/utility.js   |  4 ++--
.../misc/file_manager/static/scss/_file_manager.scss | 16 ++++++++++++++++
4 files changed, 39 insertions(+), 2 deletions(-)