[exec.task.scheduler] Move period outside of \tcode (cplusplus#8960)

Author: Andreas-Krug

source/exec.tex

@@ -7637,7 +7637,7 @@
 \begin{itemize}
 \item
 \tcode{get_completion_scheduler<set_value_t>(get_env(\exposid{ts-sndr}))}
-is equal to \tcode{*this.}
+is equal to \tcode{*this}.
 \item
 \tcode{get_completion_domain<set_value_t>(get_env(\exposid{ts-sndr}))}
 is expression-equivalent to \tcode{\exposid{ts-do\-main}()}.