cfDNA sample type abbreviation - simplify to L

[ao508]

Sample origin isn't collected anymore and other similar fields like tissueLocation aren't reliably set or filled in during sample intake.

Ronak suggested simplifying cfDNA sample type abbreviations to L, which would also mean no longer requiring sampleOrigin to be populated. To make sure that Normal samples aren't accidentally getting labeled as cfDNA though we should also exclude cases where cmoSampleIdFields.sampleType = cfDNA and sampleType (aka IGO CMO sample class) = Normal

One thing to consider:
A normal sample should always be identified as Normal (i.e., ignore that it's a cfDNA).

[ao508]

draft pr mskcc/smile-label-generator#111

[ao508]

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