Update to spec 1.26.0 and semconv 1.22.0 at the SAME time

[chalin]

• Closes Update semantic-conventions version to 1.22.0 #3387 by superseding it
• Closes Update opentelemetry-specification version to 1.26.0 #3386 by superseding it
• Updates both submodules at the same time since they are mutually dependent on each other. I suspect that this will probably always be the case but we should confirm with the spec and semconv folks.

Preview:

• https://deploy-preview-3388--opentelemetry.netlify.app/docs/specs/
• https://deploy-preview-3388--opentelemetry.netlify.app/schemas/1.22.0/

/cc @svrnm

[chalin]

An OpAMP semconv link is invalid, and is breaking the build (because we have build-time link checking for cross-spec links -- something to be revisited soon). So, atm, we're waiting on:

• [editorial] specification: fix semconv link opamp-spec#171

[svrnm]

lgtm, I'll approve this now so you can merge it when ever the dependencies are fixed

[tigrannajaryan]

So, atm, we're waiting on:

• [editorial] specification: fix semconv link opamp-spec#171

Merged.

[chalin]

So that we can get schema 1.22.0 out, I've disabled some link checks etc. I'll reenable them via:

• Post specs update: address 404s and reenabled all checks #3392