[ub.general,ifndr.general] Avoid hanging paragraphs by introducing 'General' subclauses (#7848)

Author: jensmaurer

source/ifndr.tex

@@ -1,6 +1,8 @@
 %!TEX root = std.tex
 \infannex{ifndr}{Enumeration of Ill-formed, No Diagnostic Required}
 
+\rSec1[ifndr.general]{General}
+
 This Annex documents ill-formed no diagnostic required behavior called out in the main standard text by
 the following phrases: no diagnostic is required, no diagnostic required and no diagnostic shall be issued.
 Each entry contains a title, a numeric cross reference to the main standard text, a summary of the issue

source/ub.tex

@@ -1,6 +1,8 @@
 %!TEX root = std.tex
 \infannex{ub}{Enumeration of Core Undefined Behavior}
 
+\rSec1[ub.general]{General}
+
 This Annex documents undefined behavior explicitly called out in the main standard text using the
 following phrases: the behavior of the program is undefined, has undefined behavior, results in
 undefined behavior, the behavior is undefined, have undefined behavior, is undefined, result has