run go fmt with Go 1.20 (#725)

<!--
For Work In Progress Pull Requests, please use the Draft PR feature,
see https://github.blog/2019-02-14-introducing-draft-pull-requests/ for
further details.

     For a timely review/response, please avoid force-pushing additional
     commits if your PR already received reviews or comments.

     Before submitting a Pull Request, please ensure that you have:
- 📖 Read the Contributing guide:
https://github.com/gorilla/.github/blob/main/CONTRIBUTING.md
- 📖 Read the Code of Conduct:
https://github.com/gorilla/.github/blob/main/CODE_OF_CONDUCT.md

     - Provide tests for your changes.
     - Use descriptive commit messages.
	 - Comment your code where appropriate.
	 - Squash your commits
     - Update any related documentation.

     - Add gorilla/pull-request-reviewers as a Reviewer
-->

## What type of PR is this? (check all applicable)

- [ ] Refactor
- [ ] Feature
- [ ] Bug Fix
- [ ] Optimization
- [x] Documentation Update

## Description

`go fmt` now formats godoc comments. I apply it.

## Related Tickets & Documents

<!--
For pull requests that relate or close an issue, please include them
below. We like to follow [Github's guidance on linking issues to pull
requests](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue).

For example having the text: "closes #1234" would connect the current
pull
request to issue 1234.  And when we merge the pull request, Github will
automatically close the issue.
-->

- Related Issue #
- Closes #

## Added/updated tests?

- [ ] Yes
- [x] No, and this is why: this pull request updates only comments
- [ ] I need help with writing tests

## Run verifications and test

- [x] `make verify` is passing
- [x] `make test` is passing

Co-authored-by: Corey Daley <cdaley@redhat.com>

doc.go

@@ -10,18 +10,18 @@ http.ServeMux, mux.Router matches incoming requests against a list of
 registered routes and calls a handler for the route that matches the URL
 or other conditions. The main features are:
 
-	* Requests can be matched based on URL host, path, path prefix, schemes,
-	  header and query values, HTTP methods or using custom matchers.
-	* URL hosts, paths and query values can have variables with an optional
-	  regular expression.
-	* Registered URLs can be built, or "reversed", which helps maintaining
-	  references to resources.
-	* Routes can be used as subrouters: nested routes are only tested if the
-	  parent route matches. This is useful to define groups of routes that
-	  share common conditions like a host, a path prefix or other repeated
-	  attributes. As a bonus, this optimizes request matching.
-	* It implements the http.Handler interface so it is compatible with the
-	  standard http.ServeMux.
+  - Requests can be matched based on URL host, path, path prefix, schemes,
+    header and query values, HTTP methods or using custom matchers.
+  - URL hosts, paths and query values can have variables with an optional
+    regular expression.
+  - Registered URLs can be built, or "reversed", which helps maintaining
+    references to resources.
+  - Routes can be used as subrouters: nested routes are only tested if the
+    parent route matches. This is useful to define groups of routes that
+    share common conditions like a host, a path prefix or other repeated
+    attributes. As a bonus, this optimizes request matching.
+  - It implements the http.Handler interface so it is compatible with the
+    standard http.ServeMux.
 
 Let's start registering a couple of URL paths and handlers:
 
@@ -301,6 +301,5 @@ A more complex authentication middleware, which maps session token to users, cou
 	r.Use(amw.Middleware)
 
 Note: The handler chain will be stopped if your middleware doesn't call `next.ServeHTTP()` with the corresponding parameters. This can be used to abort a request if the middleware writer wants to.
-
 */
 package mux

mux.go

@@ -31,17 +31,17 @@ func NewRouter() *Router {
 // It implements the http.Handler interface, so it can be registered to serve
 // requests:
 //
-//     var router = mux.NewRouter()
+//	var router = mux.NewRouter()
 //
-//     func main() {
-//         http.Handle("/", router)
-//     }
+//	func main() {
+//	    http.Handle("/", router)
+//	}
 //
 // Or, for Google App Engine, register it in a init() function:
 //
-//     func init() {
-//         http.Handle("/", router)
-//     }
+//	func init() {
+//	    http.Handle("/", router)
+//	}
 //
 // This will send all incoming requests to the router.
 type Router struct {