cloudfoundry-cli 6.1.0

This change updates the formula to install cloudfoundry-cli v6.1.0. It
also updates the formula to handle the new Version and BuiltOnDate
constants.
cloudfoundry-cli: add 6.1.0 bottle.

Closes #28319.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
Enable Python bindings in vte formula.
Fix trailing whitespace.
vte formula now does not assume location of pygobject-codegen-2.0
Addressed review comments
Addressed review comments
Improve comment
Python dependency is not recommended
Only "--enable-python" if `build.with? "python"`
vte: add 0.28.0 bottle.