Strip newlines from plugin pip urls on `meltano add`
As per #3393 (closed), adding a pip url with training newline characters (e.g. by using multi-line stings in YAML) causes formatting issues in meltano.yml
. This can be solved in specific cases by removing multi-line strings from discovery.yml
or in the general case by stripping leading and trailing newlines and whitespace from pip url strings during meltano add
.