feat: Use Conan 2 (#2179)

Merge right after: https://github.com/XRPLF/clio/pull/2178
Waits for: https://github.com/XRPLF/rippled/pull/5462

.github/actions/prepare_runner/action.yml

@@ -18,13 +18,13 @@ runs:
           ca-certificates \
           ccache \
           clang-build-analyzer \
-          conan@1 \
+          conan \
           gh \
           jq \
           llvm@14 \
           ninja \
           pkg-config
-        echo "/opt/homebrew/opt/conan@1/bin" >> $GITHUB_PATH
+        echo "/opt/homebrew/opt/conan@2/bin" >> $GITHUB_PATH
 
     - name: Install CMake 3.31.6 on mac
       if: ${{ runner.os == 'macOS' }}
@@ -55,14 +55,14 @@ runs:
       shell: bash
       run: |
         echo "CCACHE_DIR=${{ github.workspace }}/.ccache" >> $GITHUB_ENV
-        echo "CONAN_USER_HOME=${{ github.workspace }}" >> $GITHUB_ENV
+        echo "CONAN_HOME=${{ github.workspace }}/.conan2" >> $GITHUB_ENV
 
     - name: Set env variables for Linux
       if: ${{ runner.os == 'Linux' }}
       shell: bash
       run: |
         echo "CCACHE_DIR=/root/.ccache" >> $GITHUB_ENV
-        echo "CONAN_USER_HOME=/root/" >> $GITHUB_ENV
+        echo "CONAN_HOME=/root/.conan2" >> $GITHUB_ENV
 
     - name: Set CCACHE_DISABLE=1
       if: ${{ inputs.disable_ccache == 'true' }}
@@ -74,4 +74,4 @@ runs:
       shell: bash
       run: |
         mkdir -p "$CCACHE_DIR"
-        mkdir -p "$CONAN_USER_HOME/.conan"
+        mkdir -p "$CONAN_HOME"