fix applying --env if no TEA_DIR

Author: mxcl

README.md

@@ -3,7 +3,7 @@
 * [`install.sh`](./install.sh) is delivered when you `curl tea.xyz`.
 * This repository also provides the `tea` GitHub Action.
 
-# GitHub Action 0.18.0
+# GitHub Action 0.18.1
 
 ```yaml
 - uses: teaxyz/setup@v0

action.js

@@ -63,10 +63,12 @@ async function go() {
 
   const tea = await useCellar().resolve({project: 'tea.xyz', constraint: new semver.Range('*')})
   const teafile = tea.path.join('bin/tea').string
-  const env_args = ['--env']
+  const env_args = []
 
   if (TEA_DIR && tea.pkg.version.gte(new SemVer("0.19"))) {
-    env_args.push('--keep-going')
+    env_args.push('--env', '--keep-going')
+  } else if (TEA_DIR) {
+    env_args.push('--env')
   }
 
   let args = tea.pkg.version.gte(new SemVer("0.21"))