Upgrade rust/crates/itoa to 0.4.8

Test: make
Change-Id: Ib96e77c0e5ac556c072449e47db7527e652cd3a1
diff --git a/.clippy.toml b/.clippy.toml
new file mode 100644
index 0000000..8e17d80
--- /dev/null
+++ b/.clippy.toml
@@ -0,0 +1 @@
+msrv = "1.0.0"