Add section about versioning

Author: styfle

README.md

@@ -20,13 +20,25 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Cancel Previous Runs
-        uses: styfle/cancel-workflow-action@0.10.0
+        uses: styfle/cancel-workflow-action
       #- name: Run Tests
       #  uses: actions/setup-node@v1
       #  run: node test.js
       # ... etc
 ```
 
+### Versioning
+
+It is recommended to pin a specific version of this action so you don't automatically upgrade to the latest which could introduce breaking changes.
+
+```yml
+uses: styfle/cancel-workflow-action@0.9.1
+```
+
+Notice there is no `v` prefix, just the `@major.minor.patch` version.
+
+Visit [Releases](https://github.com/styfle/cancel-workflow-action/releases) to find the latest version at the top of the page.
+
 ### Advanced: Canceling Other Workflows
 
 In some cases, you may wish to avoid modifying all your workflows and instead create a new workflow that cancels your other workflows. This can be useful when you have a problem with workflows getting queued.
@@ -43,7 +55,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 3
     steps:
-      - uses: styfle/cancel-workflow-action@0.10.0
+      - uses: styfle/cancel-workflow-action
         with:
           workflow_id: 479426
 ```
@@ -72,7 +84,7 @@ jobs:
   cancel:
     runs-on: ubuntu-latest
     steps:
-    - uses: styfle/cancel-workflow-action@0.10.0
+    - uses: styfle/cancel-workflow-action
       with:
         workflow_id: ${{ github.event.workflow.id }}
 ```
@@ -92,7 +104,7 @@ jobs:
     timeout-minutes: 3
     steps:
       - name: Cancel build runs
-        uses: styfle/cancel-workflow-action@0.10.0
+        uses: styfle/cancel-workflow-action
         with:
           ignore_sha: true
           workflow_id: 479426
@@ -113,7 +125,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 3
     steps:
-      - uses: styfle/cancel-workflow-action@0.10.0
+      - uses: styfle/cancel-workflow-action
         with:
           all_but_latest: true
 ```
@@ -134,7 +146,7 @@ jobs:
       actions: write
     steps:
       - name: Cancel Previous Runs
-        uses: styfle/cancel-workflow-action@0.10.0
+        uses: styfle/cancel-workflow-action
         with:
           access_token: ${{ github.token }}
 ```