Update github action and README

Author: praveenperera

.github/workflows/code_coverage.yml

@@ -38,7 +38,7 @@ jobs:
       - name: Install grcov
         run: if [[ ! -e ~/.cargo/bin/grcov ]]; then cargo install grcov; fi
       - name: Test
-        run: cargo test -- --test-threads=1
+        run: cargo test --features tokio -- --test-threads=1
       - name: Run grcov
         run: mkdir coverage; grcov . --binary-path ./target/debug/ -s . -t lcov --branch --ignore-not-existing --ignore '/*' -o ./coverage/lcov.info
       - name: Generate HTML coverage report

README.md

@@ -2,6 +2,8 @@
 
 Bitcoin Esplora API client library. Supports plaintext, TLS and Onion servers. Blocking or async.
 
+If using the async client, you can choose between `tokio` or `async-std` as the runtime. One of these features must be enabled.
+
 <p>
     <a href="https://crates.io/crates/esplora-client"><img alt="Crate Info" src="https://img.shields.io/crates/v/esplora-client.svg"/></a>
     <a href="https://github.com/bitcoindevkit/rust-esplora-client/blob/master/LICENSE"><img alt="MIT Licensed" src="https://img.shields.io/badge/license-MIT-blue.svg"/></a>
@@ -25,4 +27,4 @@ cargo update -p home --precise 0.5.5
 cargo update -p url --precise "2.5.0"
 cargo update -p tokio --precise "1.38.1"
 cargo update -p tokio-util --precise "0.7.11"
-```
+```