docs: apply redirects

Those redirect, so we might as well hardcode the them.

docs/index.rst

@@ -61,7 +61,7 @@ Sponsors
   |
 
   .. image:: ../static/tembo.png
-    :target: https://tembo.io/?utm_source=sponsor&utm_campaign=postgrest
+    :target: https://www.tembo.io/?utm_source=sponsor&utm_campaign=postgrest
 
   .. container:: img-dark
 

docs/references/configuration.rst

@@ -890,7 +890,7 @@ server-timing-enabled
   **In-Database** pgrst.server_timing_enabled
   =============== =================================
 
-  Enables the `Server-Timing <https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Server-Timing>`_ header.
+  Enables the `Server-Timing <https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Server-Timing>`_ header.
   See :ref:`server-timing_header`.
 
 .. _server-unix-socket: