Doc: Remove extraneous whitespaces with some tags

Author: Justin Pryzby
Discussion: https://postgr.es/m/20210423184338.GL7256@telsasoft.com

doc/src/sgml/maintenance.sgml

@@ -719,7 +719,7 @@ HINT:  Stop the postmaster and vacuum that database in single-user mode.
     <productname>PostgreSQL</productname> has an optional but highly
     recommended feature called <firstterm>autovacuum</firstterm>,
     whose purpose is to automate the execution of
-    <command>VACUUM</command> and <command>ANALYZE </command> commands.
+    <command>VACUUM</command> and <command>ANALYZE</command> commands.
     When enabled, autovacuum checks for
     tables that have had a large number of inserted, updated or deleted
     tuples.  These checks use the statistics collection facility;

doc/src/sgml/mvcc.sgml

@@ -1074,7 +1074,7 @@ ERROR:  could not serialize access due to read/write dependencies among transact
 
 
     <table tocentry="1" id="table-lock-compatibility">
-     <title> Conflicting Lock Modes</title>
+     <title>Conflicting Lock Modes</title>
      <tgroup cols="9">
       <colspec colnum="1" colwidth="1.25*"/>
       <colspec colnum="2" colwidth="1*" colname="lockst"/>

doc/src/sgml/pgcrypto.sgml

@@ -1410,7 +1410,7 @@ gen_random_uuid() returns uuid
       <entry>KAME kame/sys/crypto</entry>
      </row>
      <row>
-      <entry>SHA256/384/512 </entry>
+      <entry>SHA256/384/512</entry>
       <entry>Aaron D. Gifford</entry>
       <entry>OpenBSD sys/crypto</entry>
      </row>

doc/src/sgml/ref/pg_rewind.sgml

@@ -25,7 +25,7 @@ PostgreSQL documentation
    <arg rep="repeat"><replaceable>option</replaceable></arg>
    <group choice="plain">
     <group choice="req">
-     <arg choice="plain"><option>-D </option></arg>
+     <arg choice="plain"><option>-D</option></arg>
      <arg choice="plain"><option>--target-pgdata</option></arg>
     </group>
     <replaceable> directory</replaceable>

doc/src/sgml/runtime.sgml

@@ -2258,7 +2258,7 @@ pg_dumpall -p 5432 | psql -d postgres -p 5433
    The certificates of <quote>intermediate</quote> certificate authorities
    can also be appended to the file.  Doing this avoids the necessity of
    storing intermediate certificates on clients, assuming the root and
-   intermediate certificates were created with <literal>v3_ca </literal>
+   intermediate certificates were created with <literal>v3_ca</literal>
    extensions.  (This sets the certificate's basic constraint of
    <literal>CA</literal> to <literal>true</literal>.)
    This allows easier expiration of intermediate certificates.