pgAdmin 4 commit: Replace the existing color picker - spectrum-colorpic

Replace the existing color picker - spectrum-colorpicker with @simonwep/pickr.

spectrum-colorpicker has accessibility issues and is not maintained since long

Part of #5197

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=824e3866d86cfcafef9394a175cd2590227a6c28
Author: Aditya Toshniwal <aditya(dot)toshniwal(at)enterprisedb(dot)com>

Modified Files
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web/package.json | 2 +-
web/pgadmin/static/css/style.css | 1 -
web/pgadmin/static/js/backform.pgadmin.js | 109 +++++++----
web/pgadmin/static/scss/_pickr.overrides.scss | 19 ++
web/pgadmin/static/scss/pgadmin.scss | 1 +
web/webpack.shim.js | 6 +-
web/webpack.test.config.js | 2 +-
web/yarn.lock | 248 ++------------------------
8 files changed, 120 insertions(+), 268 deletions(-)