Move Analyze CI job to Buildkite (#3919)

We now have two Buildkite agents thanks to a newly added M1 Mac mini
from MacStadium. Running the analyze job should be considerably faster
than the VMs that run on Azure Pipelines, although still slower than
if we were to run them with Xcode 13.2.1 because of the performance
regressions described in https://github.com/realm/SwiftLint/issues/3920.

.buildkite/pipeline.yml

@@ -3,3 +3,5 @@ steps:
     commands:
       - bundle install
       - bundle exec danger --verbose
+  - label: "Analyze"
+    command: make analyze

azure-pipelines.yml

@@ -71,15 +71,6 @@ jobs:
     - script: bundle exec pod lib lint --verbose
       displayName: pod lib lint
 
-- job: Analyze
-  pool:
-    vmImage: 'macOS-11'
-  variables:
-    DEVELOPER_DIR: /Applications/Xcode_13.2.1.app
-  steps:
-    - script: make analyze
-      displayName: Run SwiftLint Analyze
-
 - job: TSan
   pool:
     vmImage: 'macOS-11'