PHP deprecation warnings due to outdated dependency #39
Description
Current behaviour
The required version of spomky-labs/otphp causes deprecation warnings, as the version 10 requires thecodingmachine/safe up to version 2.x, which does not yet explicitly mark all nullable parameters as nullable.
Deprecated: Safe\gmdate(): Implicitly marking parameter $timestamp as nullable is deprecated, the explicit nullable type must be used [...]
Solution
Update the dependency of spomky-labs/otphp to use ^11.0 (which does not require thecodingmachine/safe any more).