chore(ffi): change hyper.h to only include first line of docs (#3373)

This will let us write much more documentation per item without worrying
about increasing the size of the hyper.h header file.

Author: seanmonstar

capi/cbindgen.toml

@@ -1,12 +1,15 @@
-# See https://github.com/eqrion/cbindgen/blob/master/docs.md#cbindgentoml for
+# See https://github.com/mozilla/cbindgen/blob/master/docs.md#cbindgentoml for
 # a list of possible configuration values.
 language = "C"
 header = """/*
- * Copyright 2021 Sean McArthur. MIT License.
+ * Copyright 2023 Sean McArthur. MIT License.
  * Generated by gen_header.sh. Do not edit directly.
+ *
+ * Full docs at: https://docs.rs/hyper/latest/hyper/ffi/index.html
  */"""
 include_guard = "_HYPER_H"
 no_includes = true
 sys_includes = ["stdint.h", "stddef.h", "stdbool.h"]
 cpp_compat = true
 documentation_style = "c"
+documentation_length = "short"