Manage default values for task parameters in deploy:git

[plopesc]

@justafish I made some extra tests locally to improve error handling when parameters are not set.

In this way the expected error messages are shown when any of the required parameters are not set and the push value is interpreted as true when it is not set or is empty.

[justafish]

@plopesc looks like the tests are failing:

task: Failed to run task "deploy:git": exit status 1
[deploy:git] Please provide a commit message
Failed to execute command ./vendor/bin/task deploy:git directory=/tmp/release branch=pr-244 remote=ssh://codeserver.dev.22fcd7e9-8dd3-4bab-8fe0-7c856b1ee202@codeserver.dev.22fcd7e9-8dd3-4bab-8fe0-7c856b1ee202.drush.in:2222/~/repository.git message="0cbcee6372d06f17240c5a941887b7a12483470a" site=***.pr-244: exit status 201
Error: Process completed with exit code 1.

[plopesc]

@justafish I misspelled the word "mesage". Typo has been fixed.

Sorry for the inconvenience.

[justafish]

Thanks!