Bump infection

Author: jakzal

Makefile

@@ -93,10 +93,10 @@ tools/deptrac:
 	curl -Ls http://get.sensiolabs.de/deptrac.phar -o tools/deptrac && chmod +x tools/deptrac
 
 tools/infection: tools/infection.pubkey
-	curl -Ls https://github.com/infection/infection/releases/download/0.13.2/infection.phar -o tools/infection && chmod +x tools/infection
+	curl -Ls https://github.com/infection/infection/releases/download/0.15.0/infection.phar -o tools/infection && chmod +x tools/infection
 
 tools/infection.pubkey:
-	curl -Ls https://github.com/infection/infection/releases/download/0.13.2/infection.phar.pubkey -o tools/infection.pubkey
+	curl -Ls https://github.com/infection/infection/releases/download/0.15.0/infection.phar.pubkey -o tools/infection.pubkey
 
 tools/box:
 	curl -Ls https://github.com/humbug/box/releases/download/3.8.4/box.phar -o tools/box && chmod +x tools/box