gnu: emacs-nov-el: Use version tag instead of commit.

* gnu/packages/emacs-xyz.scm (emacs-nov-el): Remove let binding and associated
comment; correct indentation.
[source]: Use version tag as commit identifier now that upstream has restored
this information.

Signed-off-by: Efraim Flashner <efraim@flashner.co.il>

gnu/packages/emacs-xyz.scm

@@ -12550,9 +12550,6 @@ the format.")
     (license license:gpl3+)))
 
 (define-public emacs-nov-el
-  ;; Upstream does not tag releases.  Specify raw commit hash matching the
-  ;; release.
-  (let ((commit "ea0c835c1b5e6e70293f4bd64e9c89bdc42f8596"))
   (package
     (name "emacs-nov-el")
     (version "0.3.0")
@@ -12561,7 +12558,7 @@ the format.")
        (method git-fetch)
        (uri (git-reference
              (url "https://depp.brause.cc/nov.el.git")
-               (commit commit)))
+             (commit version)))
        (file-name (git-file-name name version))
        (sha256
         (base32 "04phmm14ywgicjsl2bsg6w9rapd71vdkxdp5wp0brj6px27y85jz"))))
@@ -12599,7 +12596,7 @@ Features:
 @item Image rescaling
 @end itemize
 ")
-      (license license:gpl3+))))
+    (license license:gpl3+)))
 
 (define-public epipe
   (package