bump turbo (#19179)

The Bun build issue was caused by Turborepo passing through
`USERPROFILE` from the env. Probably need to file a bug with Bun:

```
Works:
env: USERPROFILE: undefined
CWD: `D:\a\tailwindcss\tailwindcss\packages\@tailwindcss-standalone`

Fails:
env: USERPROFILE: "C:\Users\runneradmin"
CWD: `D:\a\tailwindcss\tailwindcss\packages\@tailwindcss-standalone`
```

Author: thecrypticace

integrations/upgrade/index.test.ts

@@ -2818,7 +2818,7 @@ test(
       `,
     },
   },
-  async ({ exec, fs, expect }) => {
+  async ({ exec, root, fs, expect }) => {
     await exec('npx @tailwindcss/upgrade')
 
     let before = await fs.dumpFiles('./src/**/*.{css,html}')
@@ -2855,7 +2855,7 @@ test(
     `)
 
     // Commit the changes
-    if (isRepoDirty()) {
+    if (isRepoDirty(root)) {
       await exec('git add .')
       await exec('git commit -m "upgrade"')
     }

package.json

@@ -56,7 +56,7 @@
     "prettier-plugin-embed": "^0.5.0",
     "prettier-plugin-organize-imports": "^4.3.0",
     "tsup": "^8.5.0",
-    "turbo": "^2.5.4",
+    "turbo": "^2.6.1",
     "typescript": "^5.5.4",
     "vitest": "^2.0.5"
   },

packages/@tailwindcss-standalone/scripts/build.ts

@@ -16,6 +16,10 @@ async function buildForPlatform(triple: string, outfile: string) {
       // statically bundle the proper binaries for musl vs glibc
       cmd = cmd.env({
         PLATFORM_LIBC: triple.includes('-musl') ? 'musl' : 'glibc',
+
+        // Workaround for Bun binary downloads failing on Windows CI when
+        // USERPROFILE is passed through by Turborepo.
+        USERPROFILE: '',
       })
 
       return await cmd

packages/@tailwindcss-upgrade/src/utils/git.ts

@@ -1,8 +1,8 @@
 import { execSync } from 'node:child_process'
 
-export function isRepoDirty() {
+export function isRepoDirty(cwd?: string) {
   try {
-    let stdout = execSync('git status --porcelain', { encoding: 'utf-8' })
+    let stdout = execSync('git status --porcelain', { encoding: 'utf-8', cwd })
     return stdout.trim() !== ''
   } catch (error) {
     // If it's not a git repository we don't know if it's dirty or not. But we