Embed scatter variable in run id & directory

[mlin]

[coveralls]

Pull Request Test Coverage Report for Build 3384377828

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 13 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.08%) to 95.224%

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Files with Coverage Reduction	New Missed Lines	%
WDL/runtime/workflow.py	13	97.55%
<!--	Total:	13

Totals
Change from base Build 3384370287:	0.08%
Covered Lines:	7237
Relevant Lines:	7600

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💛 - Coveralls