Suppress errors when connecting to Buildkite

It's important the collector does not raise exceptions and cause test
suites to fail. Some customers have seen exceptions raised when
connecting to Buildkite (not a surprise as networks are complicated and
unreliable).

This PR modifies the connection process to catch all StandardErrors and
log them. Trace data will be lost; however, the customer's build will
not fail which is more important.

We also intend to address the underlying issues; however, this PR is an
important defensive measure to protect customer builds.

lib/buildkite/test_collector.rb

@@ -101,5 +101,11 @@ def self.enable_tracing!
         Buildkite::TestCollector::Uploader.tracer&.backfill(:sql, finish - start, **{ query: payload[:sql] })
       end
     end
+
+    def self.safe(&block)
+      block.call
+    rescue StandardError => e
+      logger.error("Buildkite::TestCollector received exception: #{e}")
+    end
   end
 end

lib/buildkite/test_collector/library_hooks/minitest.rb

@@ -12,4 +12,4 @@ class Minitest::Test
 
 Buildkite::TestCollector.enable_tracing!
 
-Buildkite::TestCollector::Uploader.configure
+Buildkite::TestCollector.safe { Buildkite::TestCollector::Uploader.configure }

lib/buildkite/test_collector/library_hooks/rspec.rb

@@ -12,7 +12,7 @@
   config.before(:suite) do
     config.add_formatter Buildkite::TestCollector::RSpecPlugin::Reporter
 
-    Buildkite::TestCollector::Uploader.configure
+    Buildkite::TestCollector.safe { Buildkite::TestCollector::Uploader.configure }
   end
 
   config.around(:each) do |example|

spec/test_collector_spec.rb

@@ -24,4 +24,27 @@
       expect(analytics.url).to eq "https://analytics-api.buildkite.com/v1/uploads"
     end
   end
+
+  describe ".safe" do
+    let(:logger) { TestLogger.new }
+
+    class TestLogger
+      attr_reader :errors
+
+      def initialize
+        @errors = []
+      end
+
+      def error(message)
+        @errors << message
+      end
+    end
+
+    before { Buildkite::TestCollector.logger = logger }
+
+    it "suppresses exceptions and logs them to logger.error" do
+      expect{ described_class.safe { raise "penguines dance" } }.to_not raise_error
+      expect(logger.errors).to eq(["Buildkite::TestCollector received exception: penguines dance"])
+    end
+  end
 end