Fix some cases of "the the" split across two lines.

Kevin Grittner observed that 2186b608b3
introduced a new occurence of this by copying existing text, and I
found a few more cases using grep.

Discussion: http://postgr.es/m/CADAecHWfG-K+YvocHCkrXV-ycm+eUOaaUVfYZNOnwf0pSmuQCw@mail.gmail.com

doc/src/sgml/catalogs.sgml

@@ -3783,7 +3783,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</>:<replaceable>&lt;salt&gt;<
       <entry><literal><link linkend="catalog-pg-collation"><structname>pg_collation</structname></link>.oid</literal></entry>
       <entry>
        For each column in the index key, this contains the OID of the
-       the collation to use for the index, or zero if the column is not
+       collation to use for the index, or zero if the column is not
        of a collatable data type.
       </entry>
      </row>
@@ -4771,7 +4771,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</>:<replaceable>&lt;salt&gt;<
       <entry><literal><link linkend="catalog-pg-opclass"><structname>pg_opclass</structname></link>.oid</literal></entry>
       <entry>
        For each column in the partition key, this contains the OID of the
-       the collation to use for partitioning, or zero if the column is not
+       collation to use for partitioning, or zero if the column is not
        of a collatable data type.
       </entry>
      </row>

doc/src/sgml/ddl.sgml

@@ -3165,7 +3165,7 @@ CREATE INDEX ON measurement_y2008m01 (logdate);
 
     <para>
       Normally the set of partitions established when initially defining the
-      the table are not intended to remain static.  It is common to want to
+      table are not intended to remain static.  It is common to want to
       remove old partitions of data and periodically add new partitions for
       new data. One of the most important advantages of partitioning is
       precisely that it allows this otherwise painful task to be executed

src/bin/pg_basebackup/receivelog.c

@@ -629,7 +629,7 @@ ReceiveXlogStream(PGconn *conn, StreamCtl *stream)
 			 * server had sent us half of a WAL record, when it was promoted.
 			 * The new timeline will begin at the end of the last complete
 			 * record in that case, overlapping the partial WAL record on the
-			 * the old timeline.
+			 * old timeline.
 			 */
 			uint32		newtimeline;
 			bool		parsed;