docs: Update HTTP cache references to RFC 9111 compliant implementation (#3608)

Author: bartventer

README.md

@@ -263,15 +263,18 @@ rate limit, as well as help speed up your application. `go-github` does not
 handle conditional requests directly, but is instead designed to work with a
 caching `http.Transport`.
 
-Typically, an [RFC 7234](https://datatracker.ietf.org/doc/html/rfc7234)
-compliant HTTP cache such as [gregjones/httpcache](https://github.com/gregjones/httpcache)
+Typically, an [RFC 9111](https://datatracker.ietf.org/doc/html/rfc9111)
+compliant HTTP cache such as [bartventer/httpcache](https://github.com/bartventer/httpcache)
 is recommended, ex:
 
 ```go
-import "github.com/gregjones/httpcache"
+import (
+	"github.com/bartventer/httpcache"
+	_ "github.com/bartventer/httpcache/store/memcache" //  Register the in-memory backend
+)
 
 client := github.NewClient(
-	httpcache.NewMemoryCacheTransport().Client()
+	httpcache.NewClient("memcache://"),
 ).WithAuthToken(os.Getenv("GITHUB_TOKEN"))
 ```
 

github/doc.go

@@ -144,7 +144,7 @@ rate limit, as well as help speed up your application. go-github does not
 handle conditional requests directly, but is instead designed to work with a
 caching [http.Transport].
 
-Typically, an RFC 7234 compliant HTTP cache such as https://github.com/gregjones/httpcache
+Typically, an RFC 9111 compliant HTTP cache such as https://github.com/bartventer/httpcache
 is recommended. Alternatively, the https://github.com/bored-engineer/github-conditional-http-transport
 package relies on (undocumented) GitHub specific cache logic and is
 recommended when making requests using short-lived credentials such as a

github/github.go

@@ -895,7 +895,7 @@ func (c *Client) bareDo(ctx context.Context, caller *http.Client, req *http.Requ
 	}
 
 	// Don't update the rate limits if this was a cached response.
-	// X-From-Cache is set by https://github.com/gregjones/httpcache
+	// X-From-Cache is set by https://github.com/bartventer/httpcache
 	if response.Header.Get("X-From-Cache") == "" {
 		c.rateMu.Lock()
 		c.rateLimits[rateLimitCategory] = response.Rate