[migrate] to new workflow syntax

.github/main.workflow

@@ -1,9 +0,0 @@
-workflow "Integration tests" {
-  on = "push"
-  resolves = ["Quickstart"]
-}
-
-action "Quickstart" {
-  uses = "icepuma/rust-action@master"
-  args = "cd integration-test && cargo fmt -- --check && cargo clippy -- -Dwarnings && cargo test"
-}

.github/workflows/example.yml

@@ -0,0 +1,13 @@
+name: Quickstart
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v1
+      - uses: icepuma/rust-action@master
+        with:
+          args: cd integration-test && cargo fmt -- --check && cargo clippy -- -Dwarnings && cargo test

README.md

@@ -12,14 +12,20 @@
 
 # Usage
 
-```
-workflow "Quickstart" {
-  on = "push"
-  resolves = ["Quickstart"]
-}
+In a file inside `.github/workflows/quickstart.yml`
 
-action "Quickstart" {
-  uses = "icepuma/rust-action@master"
-  args = "cargo fmt -- --check && cargo clippy -- -Dwarnings && cargo test"
-}
+```yaml
+name: Rust Example
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v1
+      - uses: icepuma/rust-action@master
+        with:
+          args: cd integration-test && cargo fmt -- --check && cargo clippy -- -Dwarnings && cargo test
 ```