MDEV-33919: Remove less standard format directive an-trap

Few man pages have less standard format directive:
.it 1 an-trap which specifying a formatting instruction
related to indentation (adds tab in man page in this)

There is no traces what an-trap should do and removing
it does not affect rendering of man page

man/myisamchk.1

@@ -38,7 +38,7 @@ with partitioned tables is not supported\&.
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br
@@ -168,7 +168,7 @@ the section called \(lqMYISAMCHK MEMORY USAGE\(rq\&.
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br

man/mysql_upgrade.1

@@ -36,7 +36,7 @@ performs a table check\&. If any problems are found, a table repair is attempted
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br
@@ -54,7 +54,7 @@ with administrator privileges\&. You can do this by running a Command Prompt as
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br

man/mysqladmin.1

@@ -396,7 +396,7 @@ shell> \fBmysqladmin password "my new password"\fR
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br

man/mysqlbinlog.1

@@ -167,7 +167,7 @@ option is given\&.
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br
@@ -424,7 +424,7 @@ USE\&. (In particular, no cross\-database updates should be used\&.)
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br
@@ -1307,7 +1307,7 @@ capability enabled\&.
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br
@@ -1981,7 +1981,7 @@ shell> \fBmysqlbinlog \-v \-\-base64\-output=DECODE\-ROWS \fR\fB\fIlog_file\fR\f
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br

man/mysqlcheck.1

@@ -101,7 +101,7 @@ with partitioned tables is not supported\&.
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br

man/mysqld_safe.1

@@ -733,7 +733,7 @@ If none of these options is given, the default is
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br

man/mysqldump.1

@@ -2345,7 +2345,7 @@ file that contains its data\&. The option value is the directory in which to wri
 .sp
 .\}
 .RS 4
-.it 1 an-trap
+.it 1
 .nr an-no-space-flag 1
 .nr an-break-flag 1
 .br