gnu: biber: Downgrade to 2.11.

Biber 2.12 is incompatible with biblatex 3.11, which is what's currently
packaged.  This is a followup to 41a010875b.

* gnu/packages/tex.scm (biber): Downgrade to 2.11.

gnu/packages/patches/biber-sortinithash.patch

@@ -17,15 +17,6 @@ index b4f641e..c6f86c7 100644
        \field{extraname}{1}
        \field{sortinit}{L}
 -      \field{sortinithash}{2c7981aaabc885868aba60f0c09ee20f}
-+      \field{sortinithash}{dad3efd0836470093a7b4a7bb756eb8c}
-       \field{labelnamesource}{author}
-       \field{labeltitlesource}{title}
-       \field{title}{The Title}
-@@ -116,7 +116,7 @@ my $ann2 = q|    \entry{ann2}{misc}{}
-       \strng{authorfullhash}{90ae96c82de92e36949bc64254bbde0c}
-       \field{extraname}{2}
-       \field{sortinit}{L}
--      \field{sortinithash}{2c7981aaabc885868aba60f0c09ee20f}
 +      \field{sortinithash}{dad3efd0836470093a7b4a7bb756eb8c}
        \field{labelnamesource}{author}
        \field{labeltitlesource}{title}

gnu/packages/tex.scm

@@ -6036,7 +6036,7 @@ (define-public perl-text-bibtex
 (define-public biber
   (package
     (name "biber")
-    (version "2.12")
+    (version "2.11")
     (source (origin
               (method git-fetch)
               (uri (git-reference
@@ -6049,7 +6049,7 @@ (define-public biber
                                        "biber-sortinithash.patch"))
               (sha256
                (base32
-                "1g1hi6zvf2hmrjly1sidjaxy5440gfqm4p7p3n7kayshnjsmlskx"))))
+                "0qgkc1k9n36yfmndwz879pak6mjphld0p85lzn9g2ng0vhxsifzz"))))
     (build-system perl-build-system)
     (arguments
      `(#:phases