Add missing dependency on opensaml-storage-impl library

It was added as a part of this commit: [1].

[1] https://github.com/pac4j/pac4j/commit/\
    d3e0fc573da42b7c00f9bb479f0439a64c53f75e

Change-Id: I63401b0825bedb126db72c0daaa151320116a54b
diff --git a/BUILD b/BUILD
index 7786b50..4dfcb48 100644
--- a/BUILD
+++ b/BUILD
@@ -21,6 +21,7 @@
         "@opensaml-soap-api//jar",
         "@opensaml-soap-impl//jar",
         "@opensaml-storage-api//jar",
+        "@opensaml-storage-impl//jar",
         "@opensaml-xmlsec-api//jar",
         "@opensaml-xmlsec-impl//jar",
         "@pac4j-core//jar",
diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index c673add..f9ae990 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -35,6 +35,13 @@
     )
 
     maven_jar(
+        name = "opensaml-storage-impl",
+        artifact = "org.opensaml:opensaml-storage-impl:" + OPENSAML_VERSION,
+        sha1 = "da2116186a10ba5e1adecf2445184bf1feb1aa1c",
+        repository = SHIBBOLETH,
+    )
+
+    maven_jar(
         name = "opensaml-saml-impl",
         artifact = "org.opensaml:opensaml-saml-impl:" + OPENSAML_VERSION,
         sha1 = "c4bce04bec8fd065bbc014a2c4003172ec612ba6",