stacks: fix for fix 'fixing' @ in exe_path (#12420)

* stacks: fix for fix 'fixing' @ in exe_path

the previous fix #11580
tried to solve the problem with the @ in the exe_path by setting this
variable empty. But the perl scripts
- append a / to the empty string and (i.e. the bin path gets /binary)
- check for file presence (problem: neither binary nor /binary are
  present)

Now I quote the @ in the exe_path.

* stacks: add refmap bugfix

recipes/stacks/2.2/build.sh

@@ -20,8 +20,11 @@ cp -p scripts/{convert_stacks.pl,extract_interpop_chars.pl} "$PREFIX/bin/"
 # after installation the exe_dir is set to the absolute binary path 
 # this is not necessary and leads to an error if there are characters 
 # like @ included (Galaxy)
+
+# furthermore a bug in ref_map v2.2 is fixed
 for i in ref_map.pl denovo_map.pl
 do
-	sed -i -e 's/\(my $exe_path\s\+= \).*/\1"";/' "$PREFIX/bin/$i"
+    sed -i -e "s/^\(my \$exe_path\s\+=[^@]\+\)/\1\\\\/" "$PREFIX/bin/$i"
+    sed -i -e "s/_alpha/-alpha/" "$PREFIX/bin/$i"
 done
 

recipes/stacks/2.2/meta.yaml

@@ -6,7 +6,7 @@ package:
   version: {{ version }}
 
 build:
-  number: 1
+  number: 2
 
 source:
   sha256: {{ hash }}