Remove changes files that are already merged in 0.4.5.x

changes/bug40287

@@ -1,4 +0,0 @@
-  o Minor bugfixes (directory authority):
-    - Now that exit relays don't allow exit connections to directory authority
-      DirPorts (network reentry), disable authorities' reachability self test
-      on the DirPort. Fixes bug 40287; bugfix on 0.4.5.5-rc.

changes/bug40298

@@ -1,3 +0,0 @@
-  o Minor bugfixes (portability):
-    - Fix a non-portable usage of "==" with "test" in the configure script.
-      Fixes bug 40298; bugfix on 0.4.5.1-alpha.

changes/ticket40295

@@ -1,3 +0,0 @@
-  o Minor bugfixes (metrics port):
-    - Fix a BUG() on the MetricsPort for an internal missing handler. Fixes bug
-      40295; bugfix on 0.4.5.1-alpha.

changes/ticket40300

@@ -1,8 +0,0 @@
-  o Minor bugfixes (relay):
-    - Remove a spammy log notice that should not have been indicating the
-      operator that its IPv4/v6 was missing but it was not. Fixes bug 40300;
-      bugfix on 0.4.5.1-alpha.
-    - Do not query the address cache early in the boot process when deciding
-      if we a relay needs to fetch early directory information from an
-      authority. This resulted in a relay falsely believing it didn't have an
-      address and thus triggering an authority fetch at each boot.

changes/ticket40309

@@ -1,3 +0,0 @@
-  o New system requirements (mallinfo() deprecated):
-    - Remove mallinfo() usage entirely. Libc 2.33+ now deprecates it. Closes
-      ticket 40309.