Travis: fix the build
Travis: fix the build

The Travis docs say that `$TRAVIS_BUILD_STAGE_NAME` is in "proper case" form:

> TRAVIS_BUILD_STAGE_NAME: The build stage in capitalized form, e.g. Test or Deploy. If a build does not use build stages, this variable is empty ("").

However, it looks like they made an (undocumented) change (probably a bug in their script handling) which means that the `$TRAVIS_BUILD_STAGE_NAME` name is now in the case as given, which in this case is _lowercase_.

This means that some of the comparisons are failing and the wrong things are executed for certain builds.

As I expect this to be a bug in Travis, I'm not changing the case for the comparisons at this time.
Instead I'm fixing this by inline fixing the case of the variable for the comparisons.

Refs:
* https://docs.travis-ci.com/user/environment-variables#default-environment-variables (near the bottom of the list)

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