CI: fix security audit (#54)

tarcieri · web-flow · commit 49dca07ab46f · 2022-08-10T08:00:42.000-06:00
`sodiumoxide` is unmaintained, however we still use it for interop
testing
diff --git a/.cargo/audit.toml b/.cargo/audit.toml
@@ -0,0 +1,2 @@
+[advisories]
+ignore = ["RUSTSEC-2021-0137"]
