Describe the bug
Mobile phone numbers in Germany start with a 0 prefix such as 0157xxxxxxx. However the preceding 0 is dropped if the country code prefix +49 is added. This is described on this wikipedia page. Therefore the related change made a while ago is not restrictive enough.

Examples
invalid:
'+49015123456789'
valid:
'+4915123456789'

Additional context
Validator.js version: 13.6.0
Node.js version: v12.15.0
OS platform: macOS