Remove broken dilos apt repo

CI is currently down because apt is unable to access the repo at
dilos.org. It is failing inside the fortanix install script which tries
to run apt-get with the error:

```
5.679 E: Failed to fetch https://apt.dilos.org/dilos/dists/dilos2/InRelease  403  Forbidden [IP: 116.202.240.188 443]
```

These lines in the Dockerfile were added when Solaris builds were merged
into dist-various-2 in #45001.
However, Solaris builds were split off in
#138699. In that PR, these lines
adding the dilos repository weren't removed.

AFAICT, these are no longer necessary.

Author: ehuss

src/ci/docker/host-x86_64/dist-various-2/Dockerfile

@@ -27,9 +27,6 @@ RUN apt-get update && apt-get build-dep -y clang llvm && apt-get install -y --no
   g++-9-arm-linux-gnueabi \
   g++-11-riscv64-linux-gnu
 
-RUN apt-key adv --batch --yes --keyserver keyserver.ubuntu.com --recv-keys 74DA7924C5513486
-RUN add-apt-repository -y 'deb https://apt.dilos.org/dilos dilos2 main'
-
 ENV \
     AR_x86_64_unknown_fuchsia=x86_64-unknown-fuchsia-ar \
     CC_x86_64_unknown_fuchsia=x86_64-unknown-fuchsia-clang \