Update minimum supported Bitcoin Core version to 28.1

.github/workflows/unittests.yml

@@ -10,7 +10,7 @@ jobs:
       matrix:
         os: [macos-13, ubuntu-latest]
         python-version: ["3.9", "3.12"]
-        bitcoind-version: ["29.2"]
+        bitcoind-version: ["28.3", "29.2"]
 
     steps:
       - uses: actions/checkout@v3

docs/INSTALL.md

@@ -136,7 +136,7 @@ If (a), then note the following two points:
 
 ##### Installing Bitcoin Core
 
-If you haven't done so yet, install Bitcoin Core, version 29.0 or newer, as described [here](https://bitcoin.org/en/full-node#windows-10). After starting it for the first time, it will start the Initial Block Download. JoinMarket cannot be used until this is finished. More information on that can be found [here](https://bitcoin.org/en/full-node#initial-block-downloadibd).
+If you haven't done so yet, install Bitcoin Core, version 28.1 or newer, as described [here](https://bitcoin.org/en/full-node#windows-10). After starting it for the first time, it will start the Initial Block Download. JoinMarket cannot be used until this is finished. More information on that can be found [here](https://bitcoin.org/en/full-node#initial-block-downloadibd).
 
 ##### Configuring Bitcoin Core
 

docs/PAYJOIN.md

@@ -39,7 +39,7 @@ So just skip those sections if you already know it.
 
 ### Preparatory step: configuring for Bitcoin Core.
 
-Joinmarket currently requires a Bitcoin Core full node, version 29.0 or newer, although it can be pruned.
+Joinmarket currently requires a Bitcoin Core full node, version 28.1 or newer, although it can be pruned.
 
 First thing to do: in `scripts/`, run:
 

docs/TESTING.md

@@ -1,6 +1,6 @@
 ### Test instructions (for developers):
 
-Work in your `jmvenv` virtual environment as for all Joinmarket work. Make sure to have [bitcoind](https://bitcoin.org/en/full-node) 29.0 or newer installed. Also need miniircd installed to the root (i.e. in your `joinmarket-clientserver` directory):
+Work in your `jmvenv` virtual environment as for all Joinmarket work. Make sure to have [bitcoind](https://bitcoin.org/en/full-node) 28.1 or newer installed. Also need miniircd installed to the root (i.e. in your `joinmarket-clientserver` directory):
 
     (jmvenv)$ cd /path/to/joinmarket-clientserver
     (jmvenv)$ git clone https://github.com/Joinmarket-Org/miniircd