Merge bitcoindevkit/bdk#1291: doc(chain,esplora): minor documentation improvements

b6a58d4f9b doc(chain,esplora): minor documentation improvements (vmammal)

Pull request description:

  * Corrects an awkward use of the word 'an'
  * Adds missing backticks, brackets in a few places

  ### Checklists

  #### All Submissions:

  * [x] I've signed all my commits
  * [x] I followed the [contribution guidelines](https://github.com/bitcoindevkit/bdk/blob/master/CONTRIBUTING.md)
  * [x] I ran `cargo fmt` and `cargo clippy` before committing

ACKs for top commit:
  danielabrozzoni:
    ACK b6a58d4f9b

Tree-SHA512: 42f12f218a9849b6fc1c8da28c4d41ca86fcc9ea52311d28f67fadbec030b6cb6986774d89a30e7a2b5ee569b08c7cfa2af71bbb9b06efacfa685dbe95820f73

crates/chain/src/keychain.rs

@@ -20,7 +20,7 @@ pub use txout_index::*;
 /// Represents updates to the derivation index of a [`KeychainTxOutIndex`].
 /// It maps each keychain `K` to its last revealed index.
 ///
-/// It can be applied to [`KeychainTxOutIndex`] with [`apply_changeset`]. [`ChangeSet] are
+/// It can be applied to [`KeychainTxOutIndex`] with [`apply_changeset`]. [`ChangeSet`]s are
 /// monotone in that they will never decrease the revealed derivation index.
 ///
 /// [`KeychainTxOutIndex`]: crate::keychain::KeychainTxOutIndex

crates/chain/src/tx_graph.rs

@@ -337,7 +337,7 @@ impl<A> TxGraph<A> {
 
     /// The transactions spending from this output.
     ///
-    /// `TxGraph` allows conflicting transactions within the graph. Obviously the transactions in
+    /// [`TxGraph`] allows conflicting transactions within the graph. Obviously the transactions in
     /// the returned set will never be in the same active-chain.
     pub fn outspends(&self, outpoint: OutPoint) -> &HashSet<Txid> {
         self.spends.get(&outpoint).unwrap_or(&self.empty_outspends)