pgAdmin 4 commit: 1) Messages tab of query tool should be clear onsubs

1) Messages tab of query tool should be clear on subsequent execution of table/view using View/Edit Data. Fixes #3608
2) Clear drop-down menu should be disabled for View/Edit Data. Fixes #3609

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=f316e0533e47144ad558de14e17b523bd1905ea3

Modified Files
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docs/en_US/release_notes_4_2.rst                      | 2 ++
web/pgadmin/static/js/sqleditor/query_tool_actions.js | 1 +
web/pgadmin/tools/sqleditor/static/js/sqleditor.js    | 4 +---
3 files changed, 4 insertions(+), 3 deletions(-)