Fix Travis grep script to use PCRE to actually match things (#47065)

Several of the greps were missing the `-P` switch which caused them to 
fail to match things. The EOL grep also wasn't working right so I 
replaced it with the one I added to TGMC.

code/modules/admin/verbs/cinematic.dm

@@ -8,4 +8,4 @@
 
 	var/datum/cinematic/choice = input(src,"Cinematic","Choose",null) as anything in subtypesof(/datum/cinematic)
 	if(choice)
-		Cinematic(initial(choice.id),world,null)
+		Cinematic(initial(choice.id),world,null)

code/modules/admin/verbs/getlogs.dm

@@ -32,4 +32,4 @@
 		else
 			return
 	to_chat(src, "Attempting to send [path], this may take a fair few minutes if the file is very large.")
-	return
+	return

code/modules/admin/verbs/onlyone.dm

@@ -28,4 +28,4 @@ GLOBAL_VAR_INIT(highlander, FALSE)
 	addtimer(CALLBACK(src, .proc/only_one), 420)
 
 /mob/living/carbon/human/proc/make_scottish()
-	mind.add_antag_datum(/datum/antagonist/highlander)
+	mind.add_antag_datum(/datum/antagonist/highlander)