Change 2.3.0 to 2.4.0 (#1253)

Co-authored-by: Justin Tieri <37750742+jtieri@users.noreply.github.com>

README.md

@@ -47,7 +47,7 @@ Additional information on how IBC works can be found [here](https://ibc.cosmos.n
 
     ```shell
     $ git clone https://github.com/cosmos/relayer.git
-    $ cd relayer && git checkout v2.3.0
+    $ cd relayer && git checkout v2.4.0
     $ make install
     ```
 
@@ -58,15 +58,15 @@ Additional information on how IBC works can be found [here](https://ibc.cosmos.n
    ```
    **Default config file location:** `~/.relayer/config/config.yaml`
 
-   By default, transactions will be relayed with a memo of `rly(VERSION)` e.g. `rly(v2.3.0)`.
+   By default, transactions will be relayed with a memo of `rly(VERSION)` e.g. `rly(v2.4.0)`.
 
    To customize the memo for all relaying, use the `--memo` flag when initializing the configuration.
 
    ```shell
    $ rly config init --memo "My custom memo"
    ```
 
-   Custom memos will have `rly(VERSION)` appended. For example, a memo of `My custom memo` running on relayer version `v2.3.0` would result in a transaction memo of `My custom memo | rly(v2.3.0)`. 
+   Custom memos will have `rly(VERSION)` appended. For example, a memo of `My custom memo` running on relayer version `v2.4.0` would result in a transaction memo of `My custom memo | rly(v2.4.0)`. 
    
    The `--memo` flag is also available for other `rly` commands also that involve sending transactions such as `rly tx link` and `rly start`. It can be passed there to override the `config.yaml` value if desired.