Fix test that uses LFE

Somehow the develop and master branches of LFE have different
commit hashes and because LFE switched its default branch to
develop the hash we use for testing became incorrect. To fix
I just switched to the develop hash of the equivalent commit.

test/plugin_dialyzer.mk

@@ -308,7 +308,7 @@ dialyzer-plt-swallow-warnings: init
 	$t $(MAKE) -C $(APP) -f erlang.mk bootstrap $v
 
 	$i "Add LFE version referring to a missing function to the list of dependencies"
-	$t perl -ni.bak -e 'print;if ($$.==1) {print "DEPS = lfe\ndep_lfe_commit = 2880c8a2a7f\n"}' $(APP)/Makefile
+	$t perl -ni.bak -e 'print;if ($$.==1) {print "DEPS = lfe\ndep_lfe_commit = d656987dc5f5e08306531ad1ce13bf9ca9ec9e5a\n"}' $(APP)/Makefile
 
 	$i "Create the PLT file"
 	$t $(DIALYZER_MUTEX) $(MAKE) -C $(APP) plt $v