chore(ci): add merge_group trigger to required workflows (#160)

## Why this should be merged

Allows ruleset-required workflows to be triggered by a merge queue, not
just the PR for the merge. Although `main` isn't a particularly "busy"
branch, a merge queue will ensure that CI passes on the exact version of
code that is about to be merged; i.e. (from the [docs]):

> The merge queue provides the same benefits as the **Require branches
to be up to date before merging** branch protection, but does not
require a pull request author to update their pull request branch and
wait for status checks to finish before trying to merge.

[docs]:
https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/configuring-pull-request-merges/managing-a-merge-queue#about-merge-queues

## How this works

Adds `merge_group` workflow trigger with [recommended
type](https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows#merge_group).

## How this was tested

N/A (worst-case it has to be reverted and another PR is temporarily
blocked).

.github/workflows/go.yml

@@ -5,6 +5,8 @@ on:
     branches: [main, "release/**"]
   pull_request:
     branches: [main, "release/**"]
+  merge_group:
+    types: [checks_requested]
   workflow_dispatch:
 
 concurrency:

.github/workflows/libevm-delta.yml

@@ -5,6 +5,8 @@ on:
     branches: [main, "release/**"]
   pull_request:
     branches: [main, "release/**"]
+  merge_group:
+    types: [checks_requested]
   workflow_dispatch:
 
 concurrency:

.github/workflows/lint.yml

@@ -5,6 +5,8 @@ on:
     branches: [main, "release/**"]
   pull_request:
     branches: [main, "release/**"]
+  merge_group:
+    types: [checks_requested]
   workflow_dispatch:
 
 permissions: