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/research/techweb/_techweb_node.dm

@@ -97,4 +97,4 @@
 	return techweb_point_display_generic(get_price(TN))
 
 /datum/techweb_node/proc/on_research() //new proc, not currently in file
-    return
+    return