Remove unnecessary 'unsign' parameter to maven_jar

Update bazlets to the latest stable-3.0 revision which removes
the 'unsign' parameter from maven_jar, and remove it from the
calls.

This parameter is no longer needed; it was originally introduced
because Gerrit core needed to patch JGit libraries for GWT, and
this was not possible when they were signed. Now we don't use GWT
any more, so it's not necessary.

Change-Id: I622f2e52849a8d734aa38fe935f8d5d9c73e4a7d

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index 88ef375..371d120 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "7a9ae377b519934c87184cc05845663ed708b69c",
+    commit = "7472a1104a37d514799100d6556445836e8efe4c",
     #local_path = "/home/<user>/projects/bazlets",
 )
 

external_plugin_deps.bzl

diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index b272d6c..5ec6933 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -9,7 +9,6 @@
         artifact = "org.eclipse.jgit:org.eclipse.jgit.http.apache:" + JGIT_VERSION,
         sha1 = "668c69822b4f54b430dd9880cc2bb13f13aa88d1",
         repository = REPO,
-        unsign = True,
         exclude = [
             "about.html",
             "plugin.properties",
@@ -21,7 +20,6 @@
         artifact = "org.eclipse.jgit:org.eclipse.jgit.lfs:" + JGIT_VERSION,
         sha1 = "153e32275cb0ccfd7f6dba89cf58392d42e16c3a",
         repository = REPO,
-        unsign = True,
         exclude = [
             "about.html",
             "plugin.properties",
@@ -33,7 +31,6 @@
         artifact = "org.eclipse.jgit:org.eclipse.jgit.lfs.server:" + JGIT_VERSION,
         sha1 = "e37339c77dd00d96269e280d582c742c424b908f",
         repository = REPO,
-        unsign = True,
         exclude = [
             "about.html",
             "plugin.properties",