Redundant CSS - Search module

[ciar4n]

Pull Request for Issue # .

Summary of Changes

Removes redundant search module CSS from Isis template.

@brianteeman Could you confirm for me that this is indeed redundant? Appears to have been part of the navbar.

Testing Instructions

Code review

Expected result

Actual result

Documentation Changes Required

[brianteeman]

yes it would appear to be unused

[ghost]

I have tested this item ✅ successfully on ca33c0a

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[ghost]

marked as "Easy Test".

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[csthomas]

I have tested this item ✅ successfully on ca33c0a

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[ghost]

RTC after two successful tests.