[ruby/syntax_suggest] Do not output "Syntax OK" when there's an error

Due to a problem with ripper we do not recognize `break` as invalid code. It's confusing that "Syntax OK" is output in that case.

When there's no syntax error, the algorithm should not say anything. The exception is in the CLI and that's for compatibility with `ruby -wc`

```
$ cat /tmp/break.rb
break
⛄️ 3.1.2 🚀 /Users/rschneeman/Documents/projects/syntax_suggest (schneems/no-syntax-not-okay-break)
$ ruby -wc /tmp/break.rb
Syntax OK
```

> Note that this is invalid, running this code will raise a Syntax error.

```
$ exe/syntax_suggest /tmp/break.rb
Syntax OK
```

Close https://github.com/ruby/syntax_suggest/pull/157

https://github.com/ruby/syntax_suggest/commit/d7bd8f03a2

2 files changed, 2 insertions, 2 deletions

diff --git a/spec/syntax_suggest/unit/api_spec.rb b/spec/syntax_suggest/unit/api_spec.rb
index 21df86bb3e..006e26fd22 100644
--- a/spec/syntax_suggest/unit/api_spec.rb
+++ b/spec/syntax_suggest/unit/api_spec.rb
@@ -25,7 +25,7 @@ module SyntaxSuggest
         io: io
       )
 
-      expect(io.string.strip).to eq("Syntax OK")
+      expect(io.string.strip).to eq("")
     end
 
     it "raises original error with warning if a non-syntax error is passed" do
diff --git a/spec/syntax_suggest/unit/display_invalid_blocks_spec.rb b/spec/syntax_suggest/unit/display_invalid_blocks_spec.rb
index c696132782..45b3e7f2e7 100644
--- a/spec/syntax_suggest/unit/display_invalid_blocks_spec.rb
+++ b/spec/syntax_suggest/unit/display_invalid_blocks_spec.rb
@@ -25,7 +25,7 @@ module SyntaxSuggest
         code_lines: search.code_lines
       )
       display.call
-      expect(io.string).to include("Syntax OK")
+      expect(io.string).to include("")
     end
 
     it "selectively prints to terminal if input is a tty by default" do