Event & Action name validation regex definitions are different in Base class

[yatki]

Expected behavior

Regex validation should be the same throughout the whole framework.

Actual behavior

Event name cannot start with a number as its stated in Event class but isValidEventName method in Base Class has different regex definition.

https://github.com/LiskHQ/lisk/blob/cd67812d1548b3f383707d64274bc9f001517896/framework/src/controller/channels/base.js#L97

https://github.com/LiskHQ/lisk/blob/cd67812d1548b3f383707d64274bc9f001517896/framework/src/controller/event.js#L3

Also isValidActionName method in Base Class has different regex definition than Action class.

Steps to reproduce

Which version(s) does this affect? (Environment, OS, etc...)