Rollup merge of #34094 - abenga:doc_changes_variable_bindings, r=steveklabnik
Rollup merge of #34094 - abenga:doc_changes_variable_bindings, r=steveklabnik

Minor changes to variable bindings chapter

* In "*... name as another binding, that's currently in scope, will ...*", *"
  that's currently in scope"* is not a parenthetical element, and the commas
  can be omitted.

* Other minor changes.

graydon/rust,aidancully/rust,graydon/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,GBGamer/rust