fix broken Google link (#1006)

Author: pjfanning

docs/src/main/paradox/routing-dsl/directives/path-directives/redirectToNoTrailingSlashIfPresent.md

@@ -21,7 +21,7 @@ or refuses to for security reasons, automatically follow redirects.
 Please note that the inner paths **MUST NOT** end with an explicit trailing slash (e.g. `"things"./`)
 for the re-directed-to route to match.
 
-A good read on the subject of how to deal with trailing slashes is available on [Google Webmaster Central - To Slash or not to Slash](https://webmasters.googleblog.com/2010/04/to-slash-or-not-to-slash.html).
+A good read on the subject of how to deal with trailing slashes is available on [Google for Developers - To Slash or not to Slash](https://developers.google.com/search/blog/2010/04/to-slash-or-not-to-slash).
 
 See also @ref[redirectToTrailingSlashIfMissing](redirectToTrailingSlashIfMissing.md) which achieves the opposite - redirecting paths in case they do *not* have a trailing slash.
 

http/src/main/scala/org/apache/pekko/http/javadsl/server/directives/PathDirectives.scala

@@ -77,7 +77,7 @@ abstract class PathDirectives extends ParameterDirectives {
    * }
    * }}}
    *
-   * For further information, refer to: http://googlewebmastercentral.blogspot.de/2010/04/to-slash-or-not-to-slash.html
+   * For further information, refer to: https://developers.google.com/search/blog/2010/04/to-slash-or-not-to-slash
    */
   def pathEndOrSingleSlash(inner: Supplier[Route]): Route = RouteAdapter {
     D.pathEndOrSingleSlash { inner.get.delegate }

http/src/main/scala/org/apache/pekko/http/scaladsl/server/directives/PathDirectives.scala

@@ -160,7 +160,7 @@ trait PathDirectives extends PathMatchers with ImplicitPathMatcherConstruction w
    *
    * For further information, refer to:
    *
-   * @see [[https://webmasters.googleblog.com/2010/04/to-slash-or-not-to-slash.html]]
+   * @see [[https://developers.google.com/search/blog/2010/04/to-slash-or-not-to-slash]]
    * @group path
    */
   def pathEndOrSingleSlash: Directive0 = rawPathPrefix(Slash.? ~ PathEnd)