Avoid skip_duplicates to prevent database locks

[samuelbray32]

Description

Fixes #1410

• transaction grouping in populate_all_common leads to long transaction times
• tables like Lab often have pre-existing entries in database
• Previously used skip_duplicates=True to avoid error
  • Led to long-held locks prevventing simultaneous session insertion by multiple users
• This instead checks validity of duplicate and skips attempting to insert entirely if present
  • Should help avoid conflicting locks between users

Checklist:

• NA If this PR should be accompanied by a release, I have updated the CITATION.cff
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