Update name of InsecureCipherMode error-prone pattern

Without this, using bazel 0.4.4 to build fails:

 ERROR: jgit/org.eclipse.jgit/BUILD:29:1: Java compilation in rule '//org.eclipse.jgit:insecure_cipher_factory' failed: Worker process sent response with exit code: 1.
 jgit/src/org/eclipse/jgit/transport/InsecureCipherFactory.java:63: error: [InsecureCryptoUsage] Insecure usage of a crypto API: the transformation is not a compile-time constant expression.
                return Cipher.getInstance(algo);
                                         ^
    (see http://errorprone.info/bugpattern/InsecureCryptoUsage)

Change-Id: I7f9a3a5117e42cb68544674f5312df0368aa3674

org.eclipse.jgit/BUILD

@@ -29,5 +29,5 @@ java_library(
 java_library(
     name = "insecure_cipher_factory",
     srcs = INSECURE_CIPHER_FACTORY,
-    javacopts = ["-Xep:InsecureCipherMode:OFF"],
+    javacopts = ["-Xep:InsecureCryptoUsage:OFF"],
 )