Fix another typo (plk#1342)

Author: moewew

doc/latex/biblatex/biblatex.tex

@@ -11800,13 +11800,13 @@ \subsection{Localization Strings}
 
 Defines the bibliography string format for \prm{setname}. The format works exactly like an additional \prm{wrapper} format for \cmd{bibstring}. \prm{code} is executed whenever a bibliography string of \prm{setname} is printed. The text of the bibliography string is passed to \prm{code} as first and only argument.
 
-\cmditem{UneclareBibstringSetFormat}{setname}
+\cmditem{UndeclareBibstringSetFormat}{setname}
 
 Remove any bibliography string set format defined for \prm{setname}.
 
 \end{ltxsyntax}
 
-Bibliography string sets can be useful to apply additional formatting to a number of bibliography strings at the same time. These commands are intended for use in language modules. For example in French typography it is customary to italicise Latin terms. The French language module can define a new bibliography string set called \texttt{latin} for all Latin strings and apply additional formatting only to these strings. It is not recommended to apply the formatting dierctly in the bibliography string definitions, since that can interfere with the capitalisation function. Assuming that the French language \texttt{.lbx} file only defines two Latin strings, \texttt{andothers} and \texttt{ibidem}, the \texttt{.lbx} file would contain.
+Bibliography string sets can be useful to apply additional formatting to a number of bibliography strings at the same time. These commands are intended for use in language modules. For example in French typography it is customary to italicise Latin terms. The French language module can define a new bibliography string set called \texttt{latin} for all Latin strings and apply additional formatting only to these strings. It is not recommended to apply the formatting directly in the bibliography string definitions, since that can interfere with the capitalisation function. Assuming that the French language \texttt{.lbx} file only defines two Latin strings, \texttt{andothers} and \texttt{ibidem}, the \texttt{.lbx} file would contain the following.
 
 \begin{ltxexample}[escapeinside={(*@}{@*)}]
 \DeclareBibliographyExtras{%