Remove restriction on base

[tonicebrian]

The restriction on base < 4.18 prevents compiling with GHC 9.6.6 and higher. I think it is safe to drop that restriction entirely.

Could you please bump this version to hackage?

[SamuelSchlesinger]

When I tried to upload this to hackage, I see:

[missing-bounds-important] The dependency 'build-depends: base' does not
specify an upper bound on the version number. Each major release of the 'base'
package changes the API in various ways and most packages will need some
changes to compile with it. The recommended practice is to specify an upper
bound on the version of the 'base' package. This ensures your package will
continue to build when a new major version of the 'base' package is released.
If you are not sure what upper bound to use then use the next major version.
For example if you have tested your package with 'base' version 4.5 and 4.6
then use 'build-depends: base >= 4.5 && < 4.7'.

[tonicebrian]

Ups sorry, I didn't know that hackage doesn't allow the uncapped base. I'll create a new PR with latest base