ci: move benchmark runners to c8id.metal-48xl

Update the bench-dedicated runner family used by the PR, develop, and
nightly benchmark workflows from c6id.metal to c8id.metal-48xl.

Signed-off-by: Joe Isaacs <joe.isaacs@live.co.uk>
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EE1ue4mLVxfSXTXUNbB8Y6

Author: joseph-isaacs

.github/workflows/develop-bench.yml

@@ -35,7 +35,7 @@ jobs:
     timeout-minutes: 120
     runs-on: >-
       ${{ github.repository == 'vortex-data/vortex'
-          && format('runs-on={0}/runner=bench-dedicated/family=c6id.metal/extras=s3-cache/tag={1}', github.run_id, matrix.benchmark.id)
+          && format('runs-on={0}/runner=bench-dedicated/family=c8id.metal-48xl/extras=s3-cache/tag={1}', github.run_id, matrix.benchmark.id)
           || 'ubuntu-latest' }}
     strategy:
       fail-fast: false

.github/workflows/nightly-bench.yml

@@ -30,4 +30,4 @@ jobs:
       matrix:
         machine_type:
           - id: x86
-            instance_name: c6id.metal
+            instance_name: c8id.metal-48xl

.github/workflows/pr-bench-runner.yml

@@ -32,7 +32,7 @@ jobs:
     timeout-minutes: 120
     runs-on: >-
       ${{ github.repository == 'vortex-data/vortex'
-          && format('runs-on={0}/runner=bench-dedicated/family=c6id.metal/tag={1}{2}', github.run_id, inputs.benchmark_id, github.event.pull_request.head.repo.fork == false && '/extras=s3-cache' || '')
+          && format('runs-on={0}/runner=bench-dedicated/family=c8id.metal-48xl/tag={1}{2}', github.run_id, inputs.benchmark_id, github.event.pull_request.head.repo.fork == false && '/extras=s3-cache' || '')
           || 'ubuntu-latest' }}
     steps:
       - uses: runs-on/action@v2

.github/workflows/sql-bench-matrix.yml

@@ -13,7 +13,7 @@ on:
       machine_type:
         required: false
         type: string
-        default: c6id.metal
+        default: c8id.metal-48xl
 
 jobs:
   resolve-matrix: