pgAdmin 4 commit: Ensure the file manager properly escapes file &direc

Ensure the file manager properly escapes file & directory names. Fixes #3196

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=9ea118ca572707cac87ee5182ec5ce1538cca22f
Author: Murtuza Zabuawala <murtuza.zabuawala@enterprisedb.com>

Modified Files
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.../feature_tests/xss_checks_file_manager_test.py  | 114 +++++++++++++++++++++
web/pgadmin/misc/file_manager/static/js/utility.js |  14 +--
web/pgadmin/tools/sqleditor/static/js/sqleditor.js |  15 +--
web/regression/feature_utils/pgadmin_page.py       |  17 +--
4 files changed, 139 insertions(+), 21 deletions(-)