Memory leaks

[shopmans]

Hello

When I enabled the pprof service using zstd compression, I saw that the heap memory continued to grow, positioning the code "github.com/klauspost/compress@v1.16.5/zstd/encoder_options.go:60". Is it a problem?

[klauspost]

@shopmans This indicates you are not consistently calling Close on your encoders when you are done using them. Even better would be to re-use them.