Update pin for bazel-toolchains to latest version

https://github.com/bazelbuild/bazel-toolchains/releases/tag/b49ba36

PiperOrigin-RevId: 178294425

BUILD

diff --git a/BUILD b/BUILD
index 76c7f52..f21bbad 100644
--- a/BUILD
+++ b/BUILD
@@ -109,6 +109,6 @@
 # Will be removed once toolchain fetching is supported.
 filegroup(
     name = "dummy_toolchain_reference",
-    srcs = ["@bazel_toolchains//configs/debian8_clang/0.2.0/bazel_0.7.0:empty"],
+    srcs = ["@bazel_toolchains//configs/debian8_clang/0.2.0/bazel_0.8.0:empty"],
     visibility = ["//visibility:public"],
 )

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index 25ae376..0de0fff 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/af4681c3d19f063f090222ec3d04108c4e0ca255.tar.gz",
-        "https://github.com/bazelbuild/bazel-toolchains/archive/af4681c3d19f063f090222ec3d04108c4e0ca255.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-toolchains/archive/b49ba3689f46ac50e9277dafd8ff32b26951f82e.tar.gz",
+        "https://github.com/bazelbuild/bazel-toolchains/archive/b49ba3689f46ac50e9277dafd8ff32b26951f82e.tar.gz",
     ],
-    strip_prefix = "bazel-toolchains-af4681c3d19f063f090222ec3d04108c4e0ca255",
-    sha256 = "d58bb2d6c8603f600d522b6104d6192a65339aa26cbba9f11ff5c4b36dedb928",
+    strip_prefix = "bazel-toolchains-b49ba3689f46ac50e9277dafd8ff32b26951f82e",
+    sha256 = "1266f1e27b4363c83222f1a776397c7a069fbfd6aacc9559afa61cdd73e1b429",
 )
 
 http_archive(