x/tools/go/packages: TestConfigFlags failures

[gopherbot]

#!watchflakes
default <- pkg == "golang.org/x/tools/go/packages" && test == "TestConfigFlags"

Issue created automatically to collect these failures.

Example (log):

--- FAIL: TestConfigFlags (0.00s)
    --- FAIL: TestConfigFlags/Modules (1.95s)
        packages_test.go:537: err: exit status 2: stderr: fatal error: all goroutines are asleep - deadlock!

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "golang.org/x/tools/go/packages" && test == "TestConfigFlags"

2023-07-18 23:25 openbsd-amd64-72 tools@84f829e2 go@cd6c4e05 x/tools/go/packages.TestConfigFlags (log)

--- FAIL: TestConfigFlags (0.00s)
    --- FAIL: TestConfigFlags/Modules (1.95s)
        packages_test.go:537: err: exit status 2: stderr: fatal error: all goroutines are asleep - deadlock!

— watchflakes

[bcmills]

Duplicate of #55161