Fix a bug in actions artifact test

[Zettat123]

This bug exists in TestActionsArtifactDownload.

gitea/tests/integration/api_actions_artifact_test.go

Lines 123 to 134 in a1f56f8

	var listResp listArtifactsResponse
	DecodeJSON(t, resp, &listResp)
	assert.Equal(t, int64(2), listResp.Count)
	// Return list might be in any order. Get one file.
	var artifactIdx int
	for i, artifact := range listResp.Value {
	if artifact.Name == "artifact-download" {
	artifactIdx = i
	break
	}
	}

We assert that listResp.Count is 2, so artifactIdx could be 0 or 1.

gitea/tests/integration/api_actions_artifact_test.go

Lines 144 to 147 in a1f56f8

	var downloadResp downloadArtifactResponse
	DecodeJSON(t, resp, &downloadResp)
	assert.Len(t, downloadResp.Value, 1)
	assert.Equal(t, "artifact-download/abc.txt", downloadResp.Value[artifactIdx].Path)

Then we assert that the length of downloadResp.Value is 1. If artifactIdx is 1 at this point, the assertion on Line 147 will throw an index out of range error.