Update pin for bazel-toolchains to latest version

https://github.com/bazelbuild/bazel-toolchains/releases/tag/f3b0970

PiperOrigin-RevId: 182058527

BUILD

diff --git a/BUILD b/BUILD
index 32b9c62..09f641a 100644
--- a/BUILD
+++ b/BUILD
@@ -111,6 +111,6 @@
 # Will be removed once toolchain fetching is supported.
 filegroup(
     name = "dummy_toolchain_reference",
-    srcs = ["@bazel_toolchains//configs/debian8_clang/0.2.0/bazel_0.8.0:empty"],
+    srcs = ["@bazel_toolchains//configs/debian8_clang/0.2.0/bazel_0.9.0:empty"],
     visibility = ["//visibility:public"],
 )

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index 0de0fff..d332c5b 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -130,11 +130,11 @@
 http_archive(
     name = "bazel_toolchains",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/bazel-toolchains/archive/b49ba3689f46ac50e9277dafd8ff32b26951f82e.tar.gz",
-        "https://github.com/bazelbuild/bazel-toolchains/archive/b49ba3689f46ac50e9277dafd8ff32b26951f82e.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-toolchains/archive/f3b09700fae5d7b6e659d7cefe0dcc6e8498504c.tar.gz",
+        "https://github.com/bazelbuild/bazel-toolchains/archive/f3b09700fae5d7b6e659d7cefe0dcc6e8498504c.tar.gz",
     ],
-    strip_prefix = "bazel-toolchains-b49ba3689f46ac50e9277dafd8ff32b26951f82e",
-    sha256 = "1266f1e27b4363c83222f1a776397c7a069fbfd6aacc9559afa61cdd73e1b429",
+    strip_prefix = "bazel-toolchains-f3b09700fae5d7b6e659d7cefe0dcc6e8498504c",
+    sha256 = "ed829b5eea8af1f405f4cc3d6ecfc3b1365bb7843171036030a31b5127002311",
 )
 
 http_archive(