make "hear about" optional, make CA certificates _not_

Dockerfile

@@ -46,6 +46,7 @@ COPY --from=gcc . /rootfs
 COPY --from=musl . /rootfs
 COPY --from=libunwind . /rootfs
 COPY --from=openssl . /rootfs
+COPY --from=ca-certificates . /rootfs
 RUN --network=none cp /web-form/target/release/website-form /rootfs/usr/bin/website-form
 
 FROM stagex/filesystem:sx2024.05.0@sha256:c504b17edae1bea8c139d058b20bebd383a0be1b4f57565d92cb578012f9c0f8 AS package

crates/web-form/src/main.rs

@@ -21,7 +21,7 @@ struct FormData {
     company_name: Option<String>,
     service: String,
     help: String,
-    hear_about: String,
+    hear_about: Option<String>,
     other_source: Option<String>,
 }