Incorrect link in samples.rst

[htjb]

I think that the line

Gaussian model dimensionality :meth:`anesthetic.samples.NestedSamples.logL_P`:raw-html:`<br />`

in samples.rst in the section on Bayesian statistics should be

Gaussian model dimensionality :meth:`anesthetic.samples.NestedSamples.d_G`:raw-html:`<br />`

as it's currently linking to docs for the posterior average of the likelihood not the model dimensionality.

[lukashergt]

Indeed, thanks @htjb, even if it is just a very small change, issues like this help tremendously in creating good docs.

Addressed in #301.