ci: mcpp 2026.8.26.1 -> 2026.8.26.2

Released and indexed. Verifies this repo against the published build rather
than against a branch.

Author: Sunrisepeak

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-24.04
     timeout-minutes: 40
     env:
-      MCPP_VERSION: 2026.8.26.1
+      MCPP_VERSION: 2026.8.26.2
       XLINGS_VERSION: v2026.8.17.2
       XLINGS_NON_INTERACTIVE: '1'
       # The branch of the specification this backend is verified against. It
@@ -246,7 +246,7 @@ jobs:
       run:
         shell: bash
     env:
-      MCPP_VERSION: 2026.8.26.1
+      MCPP_VERSION: 2026.8.26.2
       XLINGS_VERSION: v2026.8.17.2
       XLINGS_NON_INTERACTIVE: '1'
     steps: