This was removed from upstream - see envoyproxy/envoy#32872

These flags are copied from upstream's .bazelrc. The most important one here is
the `-fsized-deallocation` which was required to get CEL to compile. The rest
may not be necessary, but since they changed in upstream from 1.29 to 1.30, I
think it might be a good idea to include them.

There were some details in regex that were changed upstream that we had to
incorporate

A few upstream Envoy functions that were being called in this library needed to
be passed contexts, which required plumbing that object through the call
hierarchy. Along the way, it seemed to appear that there were a few type
signatures that were possibly not completely correct, and those have been
adjusted to get things compiling successfully.

It seems that passing string arguments constructed with the `+` operator is not
allowed in ENVOY_STREAM_LOG, and possibly other macros as well. This was my
first encounter with this error, but there might be other instances lurking
elsewhere in the repository.

The signature of this abstract class method was changed upstream - this change
reflects the fix

Interesting lesson here - when calling `fmt::format`, we must use a constexpr,
since the formatting function provides compile-time type checking. Neat!

Upstream ci calls this, so we put in a dummy target here

Co-authored-by: Nathan Fudenberg <nathan.fudenberg@solo.io>

…nsions/extensions_build_config.bzl

Co-authored-by: Nathan Fudenberg <nathan.fudenberg@solo.io>

Co-authored-by: Nathan Fudenberg <nathan.fudenberg@solo.io>

Co-authored-by: Nathan Fudenberg <nathan.fudenberg@solo.io>

This reverts commit f91e837.

Previous iterations were still using the `vformat` call so they may not have
been using the `constexpr` versino of formatting correctly