[NOREF] correct casing to sentence case for standard categories

[StevenWadeOddball]

Description

Standard category name casing didn't match the category names configured for a common milestone. This standardizes the casing so duplicate categories aren't created

Also, I added a collation to the name column to enforce case insensitivity. See this pgres documentation

How to test this change

1. Create standard categories
2. Create a common milestone that uses the standard category
3. ensure that a duplicate category is not created.

Test the case insensitive table constraint

1. Make a category
2. Make another category with exactly the same name, but different casing. Ensure that this errors

PR Author Checklist

• I have provided a detailed description of the changes in this PR.
• I have provided clear instructions on how to test the changes in this PR.
• I have updated tests or written new tests as appropriate in this PR.
• Updated the Postman Collection if necessary.

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