Implement left truncation adjustment to survival analysis

[dippindots]

Fix partial https://github.com/cbioportal/cbioportal/issues/9030

This is the algorithm part, we will get the UI part done it another PR. What is included in this pr:

• Bug fix for survival calculation (survival data order related)
• All studies still use the old algorithm (without left truncation adjustment)
• New left truncation adjustment algorithm
• Unit tests for the new left truncation adjustment algorithm