Fix QUICHE CI build.

This temporarily pins bazel to a pre-7.0 version, since Bazel 7.0 apppears to
break how we pull platform headers.

Also, this does not fix the broken tests yet, merely the compilation failures.

PiperOrigin-RevId: 594046756

.bazelversion

diff --git a/.bazelversion b/.bazelversion
new file mode 100644
index 0000000..024b066
--- /dev/null
+++ b/.bazelversion
@@ -0,0 +1 @@
+6.2.1

quiche/BUILD.bazel

diff --git a/quiche/BUILD.bazel b/quiche/BUILD.bazel
index 23fa287..cd001e1 100644
--- a/quiche/BUILD.bazel
+++ b/quiche/BUILD.bazel
@@ -78,7 +78,9 @@
         ":quiche_core",
         "@boringssl//:crypto",
         "@com_google_absl//absl/base:core_headers",
+        "@com_google_absl//absl/container:btree",
         "@com_google_absl//absl/container:flat_hash_map",
+        "@com_google_absl//absl/container:flat_hash_set",
         "@com_google_absl//absl/memory",
         "@com_google_absl//absl/status",
         "@com_google_absl//absl/status:statusor",
@@ -213,6 +215,7 @@
         "@com_google_absl//absl/functional:function_ref",
         "@com_google_absl//absl/hash",
         "@com_google_absl//absl/memory",
+        "@com_google_absl//absl/numeric:bits",
         "@com_google_absl//absl/numeric:int128",
         "@com_google_absl//absl/status",
         "@com_google_absl//absl/status:statusor",
@@ -222,7 +225,6 @@
         "@com_google_absl//absl/types:optional",
         "@com_google_absl//absl/types:span",
         "@com_google_absl//absl/types:variant",
-        "@com_google_quic_trace//quic_trace:quic_trace_cc_proto",
         "@zlib",
     ],
 )
@@ -237,6 +239,7 @@
         "@com_google_absl//absl/base:core_headers",
         "@com_google_absl//absl/container:flat_hash_map",
         "@com_google_absl//absl/container:flat_hash_set",
+        "@com_google_absl//absl/container:inlined_vector",
         "@com_google_absl//absl/memory",
         "@com_google_absl//absl/strings",
         "@com_google_absl//absl/strings:str_format",
@@ -266,6 +269,7 @@
         "@com_google_absl//absl/types:optional",
         "@com_google_absl//absl/types:span",
         "@com_google_googletest//:gtest",
+        "@com_google_quic_trace//quic_trace:quic_trace_cc_proto",
     ],
 )
 
@@ -286,6 +290,8 @@
         "@com_google_absl//absl/container:flat_hash_map",
         "@com_google_absl//absl/container:flat_hash_set",
         "@com_google_absl//absl/memory",
+        "@com_google_absl//absl/status",
+        "@com_google_absl//absl/status:statusor",
         "@com_google_absl//absl/strings",
         "@com_google_absl//absl/strings:str_format",
         "@com_google_absl//absl/types:optional",
@@ -386,12 +392,14 @@
     hdrs = io_tool_support_hdrs,
     deps = [
         ":quiche_core",
+        ":quiche_platform_default",
         ":quiche_platform_default_tools",
         ":quiche_tool_support",
         "@boringssl//:crypto",
         "@com_google_absl//absl/algorithm:container",
         "@com_google_absl//absl/base:core_headers",
         "@com_google_absl//absl/cleanup",
+        "@com_google_absl//absl/container:btree",
         "@com_google_absl//absl/container:flat_hash_map",
         "@com_google_absl//absl/container:flat_hash_set",
         "@com_google_absl//absl/memory",