docs: Update README.md

Signed-off-by: kemitix <pcampbell@kemitix.net>

README.md

@@ -13,14 +13,17 @@ jobs:
     runs-on: docker
     container:
       image:
-        git.kemitix.net/kemitix/rust:v3.0.0
+        git.kemitix.net/kemitix/rust:latest
+    strategy:
+      matrix:
+        toolchain:
+          - name: stable
+          - name: nightly
     steps:
-      - name: test with nightly
-        run: cargo +nightly test
-      - name: build with v1.74.1
-        run: cargo +1.74.1 cargo build
-      - name: test with stable
-        run: cargo test
+      - name: Test
+        run: cargo +${{ matrix.toolchain.name }} test
+      - name: Build (with stable as default)
+        run: cargo build
 ```
 
 ## Toolchains
@@ -28,8 +31,7 @@ jobs:
 The available toolchain in the image are:
 
 - `nightly` 
-- stable
-- 1.74.1
+- `stable`
 
 ## Contents
 
@@ -66,6 +68,8 @@ steps:
 
 The alpine linux install doesn't build with this dependency. You can either compile `native-tls` with the `vendored` feature, or not use `openssl`.
 
+If possible, use `rustls` instead.
+
 #### vendoered native-tls
 
 This crate *must* use the `vendored` feature in order to compile in the Alpine Linux image.