[FAB-9865] Fix markup error, "**anchor peer**s"

Bold markup can't be inserted in the middle of a string, so
change "**anchor peer**s" to "**anchor peers**".

Change-Id: Ifb03958fd97a8ed1346552a5c4a68dd306d7e347
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>

Author: rpjday

docs/source/channels.rst

@@ -11,7 +11,7 @@ Each peer that joins a channel, has its own identity given by a membership servi
 which authenticates each peer to its channel peers and services.
 
 To create a new channel, the client SDK calls configuration system chaincode
-and references properties such as **anchor peer**s, and members (organizations).
+and references properties such as **anchor peers**, and members (organizations).
 This request creates a **genesis block** for the channel ledger, which stores configuration
 information about the channel policies, members and anchor peers. When adding a
 new member to an existing channel, either this genesis block, or if applicable,