doc: remove note to update bips.md version number

It has been removed from the file.

Author: fanquake

doc/release-process.md

@@ -12,7 +12,7 @@ Release Process
 
 ### Before every major and minor release
 
-* Update [bips.md](bips.md) to account for changes since the last release (don't forget to bump the version number on the first line).
+* Update [bips.md](bips.md) to account for changes since the last release.
 * Update version in `configure.ac` (don't forget to set `CLIENT_VERSION_RC` to `0`).
 * Update manpages (see previous section)
 * Write release notes (see "Write the release notes" below).