[Spec] Fix some bad links (WICG#1143)

spec.bs

@@ -2688,7 +2688,7 @@ of this specification uses:
   * <dfn>short cooldown period</dfn> is 2 weeks.
 
 Note: More details of how these numbers are determined can be found in comments here:
-(<a href="https://github.com/WICG/turtledove/issues/632">WICG/turtledove#667</a>).
+(<a href="https://github.com/WICG/turtledove/issues/632">WICG/turtledove#632</a>).
 
 The design of downsampling [=forDebuggingOnly reports=] has three main goals:
 * Prevent sending debug reports very often to protect user privacy:
@@ -5350,7 +5350,7 @@ result of [=evaluating a bidding script=], or an [=additional bid=] provided by
 
     Issue: TODO: Check whether [=generated bid/ad descriptor=] can be moved to
     [=generated bid/bid ad=] to avoid duplication
-    (<a href="https://github.com/WICG/turtledove/issues/667">WICG/turtledove#868</a>).
+    (<a href="https://github.com/WICG/turtledove/issues/868">WICG/turtledove#868</a>).
   : <dfn>ad descriptor</dfn>
   :: An [=ad descriptor=]. Render URL and size of the bid's ad.
   : <dfn>ad component descriptors</dfn>