fix typos

Author: wgyt

README.md

@@ -132,7 +132,7 @@ or [`hashes/embedded`](https://github.com/rust-bitcoin/rust-bitcoin/tree/master/
 ### Just
 
 We support [`just`](https://just.systems/man/en/) for running dev workflow commands. Run `just` from
-your shell to see list available sub-commands.
+your shell to see a list of available sub-commands.
 
 ### Building the docs
 

bitcoin/src/consensus/encode.rs

@@ -286,7 +286,7 @@ pub trait Decodable: Sized {
     ///
     /// ### Rules for trait implementations
     ///
-    /// * Simple types that that have a fixed size (own and member fields), don't have to overwrite
+    /// * Simple types that have a fixed size (own and member fields), don't have to overwrite
     ///   this method, or be concern with it.
     /// * Types that deserialize using externally provided length should implement it:
     ///   * Make `consensus_decode` forward to `consensus_decode_bytes_from_finite_reader` with the