gnu: emacs-cdlatex: Don't use unstable tarball.

* gnu/packages/emacs-xyz.scm (emacs-cdlatex)[source]: Use GIT-FETCH and
GIT-FILE-NAME.

gnu/packages/emacs-xyz.scm

@@ -6680,14 +6680,13 @@ conversion for Emacs Lisp.")
     (version "4.7")
     (source
      (origin
-       (method url-fetch)
-       (uri (string-append
-             "https://github.com/cdominik/cdlatex/archive/"
-             version ".tar.gz"))
-       (file-name (string-append name "-" version ".tar.gz"))
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/cdominik/cdlatex.git")
+             (commit version)))
+       (file-name (git-file-name name version))
        (sha256
-        (base32
-         "0pivapphmykc6vhvpx7hdyl55ls37vc4jcrxpvs4yk7jzcmwa9xp"))))
+        (base32 "1jj9vmhc4s3ych08bjm1c2xwi81z1p20rj7bvxrgvb5aga2ghi9d"))))
     (build-system emacs-build-system)
     (propagated-inputs
      `(("emacs-auctex" ,emacs-auctex)))