Kokoro: Update doxygen to 1.9.5

Change-Id: I049a51f40a19e0eae8be67492774f8aae0df024e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/108924
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>

infra/kokoro/linux/docker.sh

@@ -79,7 +79,7 @@ CLONE_SRC_DIR="$(pwd)"
 
 using depot_tools
 using go-1.18
-using doxygen-1.8.18
+using doxygen-1.9.5
 
 status "Creating source directory '${SRC_DIR}' and build directory '${BUILD_DIR}'"
 mkdir -p ${SRC_DIR}