Unused 'stream' feature flag causes build error in bhttp

[tanyav2]

The bhttp crate fails to build due to #[cfg(feature = "stream")] attribute in bhttp/src/err.rs, but the "stream" feature is not defined in bhttp/Cargo.toml.

Error:

error: unexpected `cfg` condition value: `stream`
  --> bhttp/src/err.rs:10:11
   |
10 |     #[cfg(feature = "stream")]
   |           ^^^^^^^^^^^^^^^^^^
   |
   = note: expected values for `feature` are: `bhttp`, `default`, `http`, `read-bhttp`, `read-http`, `url`, `write-bhttp`, and `write-http`
   = help: consider adding `stream` as a feature in `Cargo.toml`

Since this feature and the corresponding error ChunkTooLarge don't appear to be used, it can simply be fixed by removing these lines:

ohttp/bhttp/src/err.rs

Lines 9 to 11 in fd72888

	#[error("a chunk of data of {0} bytes is too large")]
	#[cfg(feature = "stream")]
	ChunkTooLarge(u64),