test: fix smoke test script invoking function on the wrong region

[kruskall]

Configurable regions are supported by the terraform script bu the bash script used for smoke testing is only invoking the lambda function in the default region (eu-central-1).
Add a new output variable to retrieve the aws region in the shell script and update the lambda invocation.

[ghost]

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• Start Time: 2022-09-29T12:22:42.397+0000

• Duration: 9 min 43 sec

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Test	Results
Failed	0
Passed	164
Skipped	2
Total	166

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