pgAdmin 4 commit: 1) Fixed issue in Select2 Control,added undefined/nu

1) Fixed issue in Select2 Control, added undefined/null check.
2) Fixed the width of the delete cell.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=5dd1472d6b407b59cfe5b2c300268df4843edd7c

Modified Files
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web/pgadmin/browser/server_groups/servers/static/js/variable.js | 2 +-
web/pgadmin/static/js/backform.pgadmin.js                       | 3 ++-
2 files changed, 3 insertions(+), 2 deletions(-)