fix(actions): keep folded block scalars intact across serialization (#39787) (#39817)

Backport https://github.com/go-gitea/gitea/pull/39787 by @lunny,
including the go-yaml bump. The runner counterpart is
https://gitea.com/gitea/runner/pulls/1321.

Folded (`>`) scalars in workflows gained blank lines and had spaces
turned into newlines every time Gitea re-serialized a job.

- go-yaml main fixes the accumulating blank lines
(https://github.com/yaml/go-yaml/pull/366) and the block scalar
indentation indicators (https://github.com/yaml/go-yaml/pull/414), so
`BlockSafeString` goes away
- The job encoder no longer wraps lines, because go-yaml still wraps
more-indented lines of folded scalars and turns a space into a newline

Fixes https://github.com/go-gitea/gitea/issues/39775

models/actions/task.go

@@ -236,13 +236,13 @@ func GetRunningTaskByToken(ctx context.Context, token string) (*ActionTask, erro
 
 func makeTaskStepDisplayName(step *jobparser.Step, limit int) (name string) {
 	if step.Name != "" {
-		name = string(step.Name) // the step has an explicit name
+		name = step.Name // the step has an explicit name
 	} else {
 		// for unnamed step, its "String()" method tries to get a display name by its "name", "uses",
 		// "run" or "id" (last fallback), we add the "Run " prefix for unnamed steps for better display
 		// for multi-line "run" scripts, only use the first line to match GitHub's behavior
 		// https://github.com/actions/runner/blob/66800900843747f37591b077091dd2c8cf2c1796/src/Runner.Worker/Handlers/ScriptHandler.cs#L45-L58
-		runStr, _, _ := strings.Cut(strings.TrimSpace(string(step.Run)), "\n")
+		runStr, _, _ := strings.Cut(strings.TrimSpace(step.Run), "\n")
 		name = "Run " + util.IfZero(strings.TrimSpace(runStr), step.String())
 	}
 	return util.EllipsisDisplayString(name, limit) // database column has a length limit

models/actions/task_test.go

@@ -94,14 +94,14 @@ func TestMakeTaskStepDisplayName(t *testing.T) {
 		{
 			name: "very long name truncated",
 			jobStep: &jobparser.Step{
-				Name: jobparser.BlockSafeString(strings.Repeat("a", 300)),
+				Name: strings.Repeat("a", 300),
 			},
 			expected: strings.Repeat("a", 252) + "…",
 		},
 		{
 			name: "very long run truncated",
 			jobStep: &jobparser.Step{
-				Run: jobparser.BlockSafeString(strings.Repeat("a", 300)),
+				Run: strings.Repeat("a", 300),
 			},
 			expected: "Run " + strings.Repeat("a", 248) + "…",
 		},