New year, new copyright, new expected unknown issues with various files
that won't be covered by the script and/or will be but shouldn't change.
I'll do the details on Jan 1, but would appreciate this being
preapproved so I can actually get it merged by then.
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* telemetry: use an extra cache directory for telemetry
If the sdk's `.daml` directory is not writable, telemetry fails and
kills the IDE. We add a new assistant environment variable "DAML_CACHE".
If set, this directory is used for telemetry cache data.
Fixes#8396.
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* try creating directory
* check for already existing machine id file
* set DAML_CACHE to read-only in assistant integration tests
