Update README.md (#6)

Adds `v0.2-alpha` tag and updates examples in README.md.

Author: geball

README.md

@@ -23,7 +23,7 @@ jobs:
     name: Deploy Sanity
     steps:
       - uses: actions/checkout@v2
-      - uses: sanity-io/github-action-sanity@v0.1-alpha
+      - uses: sanity-io/github-action-sanity@v0.2-alpha
         env:
           SANITY_AUTH_TOKEN: ${{ secrets.SANITY_AUTH_TOKEN }}
         with:
@@ -51,7 +51,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - name: Export dataset
-        uses: sanity-io/github-action-sanity@v0.1-alpha
+        uses: sanity-io/github-action-sanity@v0.2-alpha
         env:
           SANITY_AUTH_TOKEN: ${{ secrets.SANITY_AUTH_TOKEN }}
         with: