vendor/golang.org/x/tools: update to a09a2fb

Notably, this includes unitchecker's -fix flag.

Also, fix one vet test that failed due to new diagnostic wording.

Change-Id: I87751083dcd9cc4b1d8dce7d54bb796c745436d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/701195
Reviewed-by: Dmitri Shuralyov <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: adonovan

src/cmd/go.mod

@@ -11,7 +11,7 @@ require (
 	golang.org/x/sys v0.35.0
 	golang.org/x/telemetry v0.0.0-20250807160809-1a19826ec488
 	golang.org/x/term v0.34.0
-	golang.org/x/tools v0.36.1-0.20250808220315-8866876b956f
+	golang.org/x/tools v0.36.1-0.20250904192731-a09a2fba1c08
 )
 
 require (

src/cmd/go.sum

@@ -22,7 +22,7 @@ golang.org/x/term v0.34.0 h1:O/2T7POpk0ZZ7MAzMeWFSg6S5IpWd/RXDlM9hgM3DR4=
 golang.org/x/term v0.34.0/go.mod h1:5jC53AEywhIVebHgPVeg0mj8OD3VO9OzclacVrqpaAw=
 golang.org/x/text v0.28.0 h1:rhazDwis8INMIwQ4tpjLDzUhx6RlXqZNPEM0huQojng=
 golang.org/x/text v0.28.0/go.mod h1:U8nCwOR8jO/marOQ0QbDiOngZVEBB7MAiitBuMjXiNU=
-golang.org/x/tools v0.36.1-0.20250808220315-8866876b956f h1:9m2Iptt9ZZU5llKDJy1XUl5d13PN1ZYV16KwOvE6jOw=
-golang.org/x/tools v0.36.1-0.20250808220315-8866876b956f/go.mod h1:WBDiHKJK8YgLHlcQPYQzNCkUxUypCaa5ZegCVutKm+s=
+golang.org/x/tools v0.36.1-0.20250904192731-a09a2fba1c08 h1:KS/PXsrK6W9NdlNu8iuCiNb7KM8UFwsh8g1BUjJ9rww=
+golang.org/x/tools v0.36.1-0.20250904192731-a09a2fba1c08/go.mod h1:n+8pplxVZfXnmHBxWsfPnQRJ5vWroQDk+U2MFpjwtFY=
 rsc.io/markdown v0.0.0-20240306144322-0bf8f97ee8ef h1:mqLYrXCXYEZOop9/Dbo6RPX11539nwiCNBb1icVPmw8=
 rsc.io/markdown v0.0.0-20240306144322-0bf8f97ee8ef/go.mod h1:8xcPgWmwlZONN1D9bjxtHEjrUtSEa3fakVF8iaewYKQ=