fixed script-07.sh

Author: TzeMingHo

individual-shell-tools/grep/script-07.sh

@@ -5,4 +5,4 @@ set -euo pipefail
 # TODO: Write a command to output, for each `.txt` file in this directory, how many lines of dialogue the Doctor has.
 # The output should show that dialogue.txt contains 6 lines, dialogue-2.txt contains 2, and dialogue-3.txt contains 0.
 
-grep -c ^Doctor *.txt
+grep -c ^Doctor: *.txt