fix clinvar delins

[leexgh]

Part of: https://github.com/cBioPortal/cbioportal/issues/8470 Clinvar delins sometimes not parsing correctly. VCF -> MAF genomic location

• delins:1,111,T,CC -> 1,111,111,T,CC
• delins:1,111,TT,C -> 1,111,112,TT,C
• ins:1,111,T,TC -> 1,111,112,-,C
• del:1,111,TC,T -> 1,112,112,C,-
• substitution:1,111,T,C -> 1,111,111,T,C