Remove altering of db constraint in migration

Naming of db constraint was altered in 01e7b01. So this would cause
issues with this migration is some environments. We won't change this
constraint and instead just wait for deprecated table to be removed
in https://tacc-main.atlassian.net/browse/WG-377

geoapi/migrations/versions/20240916_1855-968f358e102a_add_watch_variables_to_project.py

@@ -58,11 +58,7 @@ def upgrade():
     finally:
         session.close()
 
-    # Drop the unique constraint
-    op.drop_constraint('observable_data_projects_system_id_path_key', 'observable_data_projects')
-
 
 def downgrade():
     op.drop_column('projects', 'watch_users')
     op.drop_column('projects', 'watch_content')
-    op.create_unique_constraint('observable_data_projects_system_id_path_key', 'observable_data_projects', ['system_id', 'path'])