Update apt package lists before install (#1623)

Resolves tiny-pilot/tinypilot-pro#1074

This PR runs `apt-get update` before installing our Debian packages to
ensure that the APT package index is up-to-date.

I have tested this fix in TinyPilot Pro:
* tiny-pilot/tinypilot-pro#1075

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bundler/bundle/install

@@ -50,6 +50,7 @@ readonly USTREAMER_DEBIAN_PACKAGE
 TINYPILOT_DEBIAN_PACKAGE="$(ls tinypilot*.deb)"
 readonly TINYPILOT_DEBIAN_PACKAGE
 
+apt-get update
 apt-get install -y \
   "./${JANUS_DEBIAN_PACKAGE}" \
   "./${USTREAMER_DEBIAN_PACKAGE}" \