gnu: libical: Update to 3.0.8.

* gnu/packages/calendar.scm (libical): Update to 3.0.8.
[source](patches): Remove.

gnu/packages/calendar.scm

@@ -110,7 +110,7 @@ (define-public date
 (define-public libical
   (package
     (name "libical")
-    (version "3.0.7")
+    (version "3.0.8")
     (source (origin
               (method url-fetch)
               (uri (string-append
@@ -118,22 +118,7 @@ (define-public libical
                     version "/libical-" version ".tar.gz"))
               (sha256
                (base32
-                "1z33wzaazbd7drl6qbh1750whd78xl2cg0gjnxyya9m83vgndgha"))
-              (patches
-               ;; Add a patch slated for 3.0.8 which preserves backwards-
-               ;; compatibility in the icalattach_new_from_data() function,
-               ;; which accidentally changed in 3.0.7 and could break some uses.
-               ;; https://gitlab.gnome.org/GNOME/evolution-data-server/issues/185
-               ;; http://lists.infradead.org/pipermail/libical-devel/2020-January/000907.html
-               (list (origin
-                       (method url-fetch)
-                       (uri (string-append
-                             "https://github.com/libical/libical/commit/"
-                             "ae394010c889e4c185160da5e81527849f9de350.patch"))
-                       (file-name "libical-3.0.7-preserve-icalattach-api.patch")
-                       (sha256
-                        (base32
-                         "0v8qcxn8a6sh78grzxd61j9478928dx38l5mf8mkdrbxv47vmvvp")))))))
+                "0vr8s7hn8204lyc4ys5bs3j5qss4lmc9ffly2m1a59avyz5cmzh9"))))
     (build-system cmake-build-system)
     (arguments
      '(#:tests? #f ; test suite appears broken