misc: add setup-kat action (#52)

Author: lauzadis

.github/actions/setup-kat/action.yml

@@ -0,0 +1,33 @@
+name: Setup Kat
+description: >
+  Prepare kat tool for use in CI
+
+runs:
+  using: composite
+  steps:
+    - name: Install AWS CLI
+      shell: bash
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y awscli
+    - name: Set up kat
+      shell: bash
+      run: |
+        kat_version=$(aws s3 ls s3://kotlin-sdk-build-tools/kat-releases/ | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | sort -V | tail -n 1)
+        
+        if [ -z "$kat_version" ]; then
+          echo "No versions of kat were found"
+          exit 1
+        fi
+        echo "Downloading kat version $kat_version"
+        
+        aws s3 cp s3://kotlin-sdk-build-tools/kat-releases/$kat_version/kat-$kat_version.zip ./kat.zip
+        
+        echo "Unzipping kat tool"
+        unzip -qq ./kat.zip -d kat
+        
+        kat_binary_path="$PWD/kat/kat-$kat_version/bin"
+        export PATH="$kat_binary_path:$PATH"
+        echo "$kat_binary_path" >> $GITHUB_PATH
+
+        echo "Installed kat version $(kat version)" || (echo "Failed to execute kat command" && exit 1)