Insensitive Like Operator

[MRichards99]

Description:
Just an issue for the action in ral-facilities/datagateway#731.

Once icatproject/python-icat#86 has been solved, closed and merged, I need to update the like operator on DataGateway API to pass UPPER() into query. This will make our like operator case insensitive on production ICATs which use Oracle databases.

I already have these changes in a stash so I just need to write some tests to prove the where filter stores the upper function.

Acceptance criteria:

• Update like operator to use SQL upper function
• Add some tests to explicitly test this within the where filter

[MRichards99]

Blocked until icatproject/python-icat#86 is closed.