chore(deps): bump vrl to latest main (#25398)

* chore(deps): bump vrl to latest main

Picks up new commits on the vrl `main` branch. The bump introduces
a new `allow_lossy_string_coercion` field on `vrl::protobuf::encode::Options`;
set to `true` in all call sites to preserve current Vector behavior
(matches vrl's default).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* chore(deps): add allow_lossy_string_coercion to OTLP e2e helper

Same vrl::protobuf::encode::Options change as the codec serializers,
applied to the e2e-tests-opentelemetry helper so that target also
compiles with the bumped vrl revision.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

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Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>