k, this is a little gross but I see no other way

.github/workflows/ci.yml

@@ -1,6 +1,7 @@
 on:
   pull_request:
     paths:
+      - action.yml
       - install.sh
       - .github/workflows/ci.yml
 

action.js

@@ -0,0 +1,8 @@
+const { execSync } = require('child_process')
+
+try {
+  console.info("Installing tea…")
+  execSync(`${__dirname}/install.sh`, [], {stdio: "inherit"})
+} catch (err) {
+  console.error(err)
+}

action.yml

@@ -2,7 +2,5 @@ name: tea/setup
 description: >
   Installs https://tea.xyz to your GitHub Actions runner.
 runs:
-  using: composite
-  steps:
-    - run: ./install.sh
-      shell: bash
+  using: node16
+  main: action.js

install.sh

@@ -46,7 +46,7 @@ elif [ -n "$TEA_SECRET" ]; then
     exec /usr/local/bin/tea "$@"
   fi
 else
-  if [ "x$PAGER" == "x" ]; then
+  if test x$PAGER = x; then
     PAGER=cat
   fi
   curl -Ssf https://raw.githubusercontent.com/teaxyz/white-paper/main/white-paper.md | $PAGER