Configurable default timeout

[smwltr]

Describe the feature:
I would like to be able to set the timeout for all tests in one place, rather than having a timeout entry for each test. IIUC, the default timeout is not configurable.

Describe the solution you'd like
I would like to be able to override the default timeout value either with a parameter from the command line, a environment variable,

Describe alternatives you've considered
sed