v0.51.0

What's Changed

• Synchronize common files from prometheus/prometheus by @prombot in #604
• expfmt: Add a way to generate different OpenMetrics Formats by @ywwg in #596
• Fix string slice definition for FormatFlagOptions. by @gizmoguy in #607
• Correct logic in sample naming for counters, add new test by @vesari in #608

New Contributors

• @gizmoguy made their first contribution in #607

Full Changelog: v0.50.0...v0.51.0