Append TES Tasks to a JSONL file

[MattMcL4475]

Problem:
TES Task data is difficult to retrieve for end users

Solution:
Serialize each TES task when it reaches a terminal state to JSON, add a newline to the end, and append it to a blob in tes-internal called "testasks0.jsonl". Once that blob reaches 50K blocks, use "testasks1.jsonl" etc.