gnu: tzdata: Update to 2019b.

* gnu/packages/base.scm (tzdata): Update to 2019b.

gnu/packages/base.scm

@@ -1215,7 +1215,7 @@ command.")
 (define-public tzdata
   (package
     (name "tzdata")
-    (version "2019a")
+    (version "2019b")
     (source (origin
              (method url-fetch)
              (uri (string-append
@@ -1223,7 +1223,7 @@ command.")
                    version ".tar.gz"))
              (sha256
               (base32
-               "0wlpqm4asvi0waaz24xj20iq40gqfypmb4nldjhkfgm09bgnsdlh"))))
+               "0r0clnlslwm15m1c61dinf1fi9ffgl6aipng7i7yryfwj0n0kn85"))))
     (build-system gnu-build-system)
     (arguments
      '(#:tests? #f
@@ -1273,7 +1273,7 @@ command.")
                                 version ".tar.gz"))
                           (sha256
                            (base32
-                            "1x9z8fpgnhzlsnps0hamb54ymaskjab7ys9m4i4gpk9hpiig2fc7"))))))
+                            "0vbmswvv3li25s31shyllq5v24449lxnrki9hr043nipjd09sirf"))))))
     (home-page "https://www.iana.org/time-zones")
     (synopsis "Database of current and historical time zones")
     (description "The Time Zone Database (often called tz or zoneinfo)