docs: fix incorrect package description in string/left-trim-n

PR-URL: #2736

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Signed-off-by: Snehil Shah <snehilshah.989@gmail.com>
Reviewed-by: Philipp Burckhardt <pburckhardt@outlook.com>
Reviewed-by: Athan Reines <kgryte@gmail.com>

Author: Snehil-Shah

lib/node_modules/@stdlib/string/left-trim-n/README.md

@@ -20,7 +20,7 @@ limitations under the License.
 
 # ltrimN
 
-> Trim `n` characters from the end of a string.
+> Trim `n` characters from the beginning of a string.
 
 <!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->