Accumulated small fixes (#26157)
* remove extra triple backtick in using docstring
* from 24074: clarify that the docstring is added to the `Function`
* prodcuts -> products
* slightly change wording in egal docstring, see review comment in 24149
* docstring fix for matmul
* missed space from review comment in 24922
* fix rendering of broadcast_getindex docs
* clean up text files from running doctests and remove some weird indentation
* remove deprecated repmat from LinearAlgebra docs
* lower case function and method in documentation docs
