contrib: stop caching appsec.Enabled() value for gin/echo

[Hellzy]

What does this PR do?

Explicitely call appsec.Enabled() every time we want to check that appsec is enabled, instead of calling
it once and only using the cached value.

Motivation

Appsec can now be enabled at runtime through remote configuration meaning that the value returned by appsec.Enabled()
can change during execution. Explicitely calling appsec.Enabled() makes sure the actual value used in our conditions is accurate.

Describe how to test/QA your changes

Reviewer's Checklist

• If known, an appropriate milestone has been selected; otherwise the Triage milestone is set.
• Changed code has unit tests for its functionality.
• If this interacts with the agent in a new way, a system test has been added.

[pr-commenter]

Benchmarks

Comparing candidate commit e030b3e in PR branch francois.mazeau/appsec-enabled-check with baseline commit f98f668 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 6 cases.

[Julio-Guerra]

Thanks, remote activation is saved ;-p