fix: Fix case sensitivity for drm content type

[Stansbridge]

This fixes the case sensitivity in the DrmEngine willSupport method. This comparison should be case insensitive, particularly for codec profiles described in hex which may be either lower or upper case. The change normalizes both the stored content types and the method arguments.

edit: Will likely target this for 2.5 as this release is the one directly affecting me.

Closes #2799

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[Stansbridge]

@googlebot I signed it!

[Stansbridge]

Closing this while I investigate a subsequent issue

[joeyparrish]

This can be cherry-picked to v2.5.x and v3.0.x. Thank you!