chore: update redirects to add anchors (#1757)

Author: desimone

static/_redirects

@@ -6,7 +6,7 @@ http://docs.pomerium.io/* https://docs.pomerium.com/:splat 301!
 https://docs.pomerium.io/* https://docs.pomerium.com/:splat 301!
 
 # Root => /docs
-/ /docs
+/ /docs 301!
 
 # Releases & Versions
 /docs/releases /docs/versions
@@ -234,12 +234,12 @@ https://docs.pomerium.io/* https://docs.pomerium.com/:splat 301!
 /docs/manage/troubleshooting.html /docs/internals/troubleshooting
 
 # Additional old capabilities => new locations
-/docs/capabilities/rego /docs/internals/ppl
+/docs/capabilities/rego /docs/internals/ppl#rego
 /docs/capabilities/namespacing /docs/internals/namespacing
-/docs/capabilities/load-balancing /docs/capabilities/routing
+/docs/capabilities/load-balancing /docs/capabilities/routing#load-balancer
 /docs/capabilities/device-identity /docs/integrations/device-context/device-identity
-/docs/capabilities/single-sign-out /docs/capabilities/authentication
-/docs/capabilities/mtls-clients /docs/internals/mutual-auth
-/docs/capabilities/mtls-services /docs/internals/mutual-auth
-/docs/capabilities/hosted-authenticate-service /docs/deploy/cloud/install
-/docs/capabilities/self-hosted-authenticate-service /docs/capabilities/authentication
+/docs/capabilities/single-sign-out /docs/capabilities/authentication#single-sign-out-sso
+/docs/capabilities/mtls-clients /docs/internals/certificates-and-tls#downstream-tls
+/docs/capabilities/mtls-services /docs/internals/certificates-and-tls#upstream-tls
+/docs/capabilities/hosted-authenticate-service /docs/capabilities/authentication#hosted-authenticate-service
+/docs/capabilities/self-hosted-authenticate-service /docs/capabilities/authentication#self-hosted-authenticate-service