Validation error when more than one space follows the subject change type

[stathismor]

When validating the subject, two spaces after the colon throw an error. This is a bit too strict and should probably be allowed and still considered a valid change type.

Example (https://ci.balena-dev.com/builds/1049419):

Validating commit: 8232e7952bb636cedce393211b03c77c591263f9

patch:  Updating the outdated screencaps in Account Management

Found the following errors:

Error: The commit subject must not start with a leading space