don't list non-stable releases in ReleaseNotes

(the idea is that ReleaseNotes is for learning what you get when you
move from one stable to another, whereas ChangeLog is for learning what
changed in each released version of tor.)

ReleaseNotes

@@ -2,72 +2,6 @@ This document summarizes new features and bugfixes in each stable
 release of Tor. If you want to see more detailed descriptions of the
 changes in each development snapshot, see the ChangeLog file.
-Changes in version 0.4.7.4-alpha - 2022-02-25
-  This version contains the negotiation congestion control work which is the
-  final part needed before going stable. There are also various bugfixes
-  including two major ones detailed below. Last, the Exit notice page layout
-  has been modernized but the text is unchanged. We recommend that all relay
-  operators running any previous alpha upgrade to this one.
-
-  o Major features (relay, client, onion services):
-    - Implement RTT-based congestion control for exits and onion
-      services, from Proposal 324. Disabled by default. Enabled by the
-      'cc_alg' consensus parameter. Closes ticket 40444.
-
-  o Major bugfixes (client):
-    - Stop caching TCP connect failures to relays/bridges when we
-      initiated the connection as a client. Now we only cache connect
-      failures as a relay or bridge when we initiated them because of an
-      EXTEND request. Declining to re-attempt the client-based
-      connections could cause problems when we lose connectivity and try
-      to reconnect. Fixes bug 40499; bugfix on 0.3.3.4-alpha.
-
-  o Major bugfixes (relay, overload):
-    - Do not trigger a general overload on DNS timeout. Even after
-      fixing 40527, some code remained that triggered the overload.
-      Fixes bug 40564; bugfix on 0.4.7.1-alpha.
-
-  o Minor feature (authority, relay):
-    - Reject End-Of-Life relays running version 0.3.5.x. Closes
-      ticket 40559.
-
-  o Minor features (fallbackdir):
-    - Regenerate fallback directories generated on February 25, 2022.
-
-  o Minor features (geoip data):
-    - Update the geoip files to match the IPFire Location Database, as
-      retrieved on 2022/02/25.
-
-  o Minor bugfix (logging):
-    - Update a log notice dead URL to a working one. Fixes bug 40544;
-      bugfix on 0.3.5.1-alpha.
-
-  o Minor bugfix (relay):
-    - Remove the HSDir and HSIntro onion service v2 protocol versions so
-      relay stop advertising that they support them. Fixes bug 40509;
-      bugfix on 0.3.5.17.
-
-  o Minor bugfixes (cell scheduling):
-    - Avoid writing empty payload with NSS write.
-    - Don't attempt to write 0 bytes after a cell scheduling loop. No
-      empty payload was put on the wire. Fixes bug 40548; bugfix
-      on 0.3.5.1-alpha.
-
-  o Minor bugfixes (compilation):
-    - Resume being able to build on old / esoteric gcc versions. Fixes
-      bug 40550; bugfix on 0.4.7.1-alpha.
-
-  o Minor bugfixes (compiler warnings):
-    - Fix couple compiler warnings on latest Ubuntu Jammy. Fixes bug
-      40516; bugfix on 0.3.5.1-alpha.
-
-  o Documentation:
-    - Provide an improved version of the tor-exit-notice.html file for
-      exit relays to use as a landing page. The text is unchanged, but
-      the page design and layout are significantly modernized, and
-      several links are fixed. Patch from "n_user"; closes ticket 40529.
-
-
 Changes in version 0.4.6.10 - 2022-02-04
   This version contains minor bugfixes but one in particular is that relays
   don't advertise onion service v2 support at the protocol version level.