Revert "bazel: Use canonical reproducible load_bazlets rule"

This reverts commit 5e3a41afdd98896d2f9d3279f1e5a144ca051379.

Since bazel v6.1.0 the warning about shallow_since has been removed
since it was determined [1] to be potentially harmful to build
performance and reliability.

[1] https://github.com/bazelbuild/bazel/issues/12857

Change-Id: Id9b44d260688b706a15be5df20d5a80e0968c548
diff --git a/WORKSPACE b/WORKSPACE
index 63c82f5..b648483 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -4,7 +4,6 @@
 
 load_bazlets(
     commit = "b6120a9fa50945d38f0a4d55d5879e3ec465c5e5",
-    shallow_since = "1701477032 -0700",
 )
 
 load(
diff --git a/bazlets.bzl b/bazlets.bzl
index 457bfec..f089af4 100644
--- a/bazlets.bzl
+++ b/bazlets.bzl
@@ -4,14 +4,12 @@
 
 def load_bazlets(
         commit,
-        shallow_since = None,
         local_path = None):
     if not local_path:
         git_repository(
             name = NAME,
             remote = "https://gerrit.googlesource.com/bazlets",
             commit = commit,
-            shallow_since = shallow_since,
         )
     else:
         native.local_repository(