pgAdmin 4 commit: Fixed broken tags and tokenizer options of select2. R

Fixed broken tags and tokenizer options of select2. Regression of #5038

With the change of data adapter, we have configured adapters for tags and tokenizers.
We also renamed the method onDemandLoad to showOnScroll to avoid confusion.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=d4ee8692818beba4f564289f6db1b6986397ca98
Author: Aditya Toshniwal <aditya.toshniwal@enterprisedb.com>

Modified Files
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web/pgadmin/browser/static/js/node.ui.js           |  51 -----------
web/pgadmin/static/js/backform.pgadmin.js          |  17 +---
web/pgadmin/static/js/backgrid.pgadmin.js          |  15 ++-
.../static/js/select2/configure_show_on_scroll.js  | 101 +++++++++++++++++++++
4 files changed, 112 insertions(+), 72 deletions(-)