[wasm] improve testing InvariantTimezone

[pavelsavara]

• add a test for wasi/single file
• add a test presence of timezone archive in bin/obj?

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Issue Details

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• add a test for wasi/single file
• add a test presence of timezone archive in bin/obj?

Author:	pavelsavara
Assignees:	-
Labels:	arch-wasm, area-Build-mono
Milestone:	Future