Replace `which` by `command -v` in aspell dictionary

The `which` command is not always available, so we use `command -v`
instead. An issue was opened upstream in
https://github.com/GNUAspell/aspell-lang/issues/3 , and a PR was
proposed but not yet accepted.

See merge request !1761

component/aspell/aspell-en_configure_which.patch

+# See https://github.com/GNUAspell/aspell-lang/issues/3
+
+--- a/configure
++++ b/configure
+@@ -79,9 +79,9 @@
+ datadir=`$ASPELL dump config data-dir`
+ echo $datadir
+ 
+-echo "ASPELL = `which $ASPELL`" > Makefile
++echo "ASPELL = `command -v $ASPELL`" > Makefile
+ echo "ASPELL_FLAGS = $ASPELL_FLAGS" >> Makefile
+-echo "PREZIP = `which $PREZIP`" >> Makefile
++echo "PREZIP = `command -v $PREZIP`" >> Makefile
+ echo "DESTDIR = $DESTDIR" >> Makefile
+ echo "dictdir = $dictdir" >> Makefile
+ echo "datadir = $datadir" >> Makefile
\ No newline at end of file

component/aspell/buildout.cfg

@@ -46,3 +46,8 @@ make-options = -j1
 <= aspell-dictionary-common
 url = ftp://ftp.gnu.org/gnu/aspell/dict/en/aspell6-en-7.1-0.tar.bz2
 md5sum = beba5e8f3afd3ed1644653bb685b2dfb
+patch-options = -p1
+patches =
+  ${:_profile_base_location_}/aspell-en_configure_which.patch#97e9fc81d5612634e9b8224b20855698
+environment =
+  PATH=${patch:location}/bin:%(PATH)s