Train-data-creator doesn't use SYMBOL ID's

[SietsmaRJ]

Describe the bug

Currently, due to limitations of supplied data, train-data-creator doesn't use SYMBOL ID's, but instead relies on (not-normalized) SYMBOL to map back a variant after being annotated by VEP. This could potentially cause issues as SYMBOL ID's are set, but SYMBOL is not, so SYMBOL could change at any minute.

System information

• OS: [e.g. iOS]
• Version: [e.g. 3.0.0]
• Python version: [e.g. Python3.9.1]
• Shell: [e.g. ZSH]

How to Reproduce

Steps to reproduce the behavior:

1. cd to dir [...]
2. Run the command [...]
3. See error.

Expected behavior

train-data-creator uses SYMBOL ID's instead of SYMBOL. This means that process-vep should also take this into account, although mapping 1 to 1 (or 1 to many: #54 ) should not limit the use of SYMBOL ID's.

Logs

If available, the generated logging information and/or error message (can also be attached as a file if very large).

Screenshots

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Additional context

#51 (comment)