Reorganize account data, receipts and presence request regexps in generic_worker docs (#17954)

POST requests for account data, receipts and presence require the worker
to be configured as a stream writer. The regular expressions in the
default list don't assume any HTTP method, so if the worker is not a
stream writer, the request fails.

The stream writer section of the documentation lists the same regexps as
the one I'm removing, so people configuring stream writers can still
configure their routing properly.

More context:
#17243 (comment)

Author: evoL

changelog.d/17954.doc

@@ -0,0 +1 @@
+Update `synapse.app.generic_worker` documentation to only recommend `GET` requests for stream writer routes by default, unless the worker is also configured as a stream writer. Contributed by @evoL.

docs/workers.md

@@ -273,17 +273,6 @@ information.
     ^/_matrix/client/(api/v1|r0|v3|unstable)/knock/
     ^/_matrix/client/(api/v1|r0|v3|unstable)/profile/
 
-    # Account data requests
-    ^/_matrix/client/(r0|v3|unstable)/.*/tags
-    ^/_matrix/client/(r0|v3|unstable)/.*/account_data
-
-    # Receipts requests
-    ^/_matrix/client/(r0|v3|unstable)/rooms/.*/receipt
-    ^/_matrix/client/(r0|v3|unstable)/rooms/.*/read_markers
-
-    # Presence requests
-    ^/_matrix/client/(api/v1|r0|v3|unstable)/presence/
-
     # User directory search requests
     ^/_matrix/client/(r0|v3|unstable)/user_directory/search$
 
@@ -292,6 +281,13 @@ Additionally, the following REST endpoints can be handled for GET requests:
     ^/_matrix/client/(api/v1|r0|v3|unstable)/pushrules/
     ^/_matrix/client/unstable/org.matrix.msc4140/delayed_events
 
+    # Account data requests
+    ^/_matrix/client/(r0|v3|unstable)/.*/tags
+    ^/_matrix/client/(r0|v3|unstable)/.*/account_data
+
+    # Presence requests
+    ^/_matrix/client/(api/v1|r0|v3|unstable)/presence/
+
 Pagination requests can also be handled, but all requests for a given
 room must be routed to the same instance. Additionally, care must be taken to
 ensure that the purge history admin API is not used while pagination requests