acc: add Ignore setting to config (#2405)

Ignore output files using gitignore syntax.

## Changes
New Ignore setting in test.toml that will ignore specified files (syntax
is gitignore).

## Why

I'm using it in #2396 to ignore virtual env. It includes a lot of files.
The regular 'rm -fr .venv' approach only works if script get to that
point, but due to errors it might abort early. In that cases test runner
prints all unexpected files, polluting output. Ignoring those files at
test runner level ensure you never see them.

## Tests
Updated selftest/basic.

acceptance/acceptance_test.go

@@ -390,6 +390,9 @@ func runTest(t *testing.T, dir, coverDir string, repls testdiff.ReplacementsCont
 		if _, ok := Ignored[relPath]; ok {
 			continue
 		}
+		if config.CompiledIgnoreObject.MatchesPath(relPath) {
+			continue
+		}
 		unexpected = append(unexpected, relPath)
 		if strings.HasPrefix(relPath, "out") {
 			// We have a new file starting with "out"

acceptance/config_test.go

@@ -11,6 +11,7 @@ import (
 	"github.com/BurntSushi/toml"
 	"github.com/databricks/cli/libs/testdiff"
 	"github.com/databricks/cli/libs/testserver"
+	ignore "github.com/sabhiram/go-gitignore"
 	"github.com/stretchr/testify/require"
 )
 
@@ -51,6 +52,11 @@ type TestConfig struct {
 
 	// List of request headers to include when recording requests.
 	IncludeRequestHeaders []string
+
+	// List of gitignore patterns to ignore when checking output files
+	Ignore []string
+
+	CompiledIgnoreObject *ignore.GitIgnore
 }
 
 type ServerStub struct {
@@ -111,6 +117,8 @@ func LoadConfig(t *testing.T, dir string) (TestConfig, string) {
 		}
 	}
 
+	result.CompiledIgnoreObject = ignore.CompileIgnoreLines(result.Ignore...)
+
 	return result, strings.Join(configs, ", ")
 }
 

acceptance/selftest/basic/script

@@ -27,3 +27,7 @@ echo 123456
 
 printf "\n=== Testing --version"
 trace $CLI --version
+
+touch ignored_file.txt
+mkdir ignored_dir
+touch ignored_dir/hello.txt

acceptance/selftest/basic/test.toml

@@ -1,5 +1,8 @@
 # Badness = "Brief description of what's wrong with the test output, if anything"
 
+Ignore = ['ignore*']
+
+
 #[GOOS]
 # Disable on Windows
 #windows = false