Import file extension is case sensitive

[maheese]

Overview: When importing JSON files, ".json" case sensitivity changes will cause import failure.

Steps to reproduce:

• Download a valid JSON monitoring plan from ECMPS 2.0
• Change the JSON file's extension from ".json" to ".JSON" or "Json" (anything other than all lower-case letters)
• Import the modified Monitoring Plan into ECMPS 2.0

Expected: The Monitoring plan should import

Observed: The Monitoring plan fails to import with the following error message: "Only JSON files may be submitted"

This is from Request Tracker ticket #74532

[ibarra-michelle]

@annalbrecht - could we relabel this from P-1B to 2025 (Q1 or Q2)? Internally, we discussed this ticket and are prioritizing other functionality. If the dev team has any questions, we can discuss them at the next meeting.