'config substitute-path' is cached, even after -clear

[thockin]

Observe:

$ dlv exec ./_output/bin/kubectl
Warning: no debug info found, some functionality will be missing such as stack traces and variable evaluation.
Type 'help' for list of commands.

(dlv) c main.main
Breakpoint 1 set at 0x1a21080 for main.main() k8s.io/kubernetes/cmd/kubectl/kubectl.go:28
> main.main() k8s.io/kubernetes/cmd/kubectl/kubectl.go:28 (hits total:1) (PC: 0x1a21080)

(dlv) config substitute-path k8s.io/kubernetes .

(dlv) list
> main.main() ./cmd/kubectl/kubectl.go:28 (PC: 0x1a21080)
    18:	
    19:	import (
    20:	... "k8s.io/component-base/cli"
    21:	... "k8s.io/kubectl/pkg/cmd"
    22:	... "k8s.io/kubectl/pkg/cmd/util"
    23:	
    24:	... // Import to initialize client auth plugins.
    25:	... _ "k8s.io/client-go/plugin/pkg/client/auth"
    26:	)
    27:	
=>  28:	func main() {
    29:	... command := cmd.NewDefaultKubectlCommand()
    30:	... if err := cli.RunNoErrOutput(command); err != nil {
    31:	... ... // Pretty-print the error and exit with an error.
    32:	... ... util.CheckErr(err)
    33:	... }
    34:	}
(dlv) exit

But if I make a mistake, then fix it, it doesn't work:

$ dlv exec ./_output/bin/kubectl
Warning: no debug info found, some functionality will be missing such as stack traces and variable evaluation.
Type 'help' for list of commands.

(dlv) c main.main
Breakpoint 1 set at 0x1a21080 for main.main() k8s.io/kubernetes/cmd/kubectl/kubectl.go:28

main.main() k8s.io/kubernetes/cmd/kubectl/kubectl.go:28 (hits total:1) (PC: 0x1a21080)

(dlv) config substitute-path k8s.io/kubernetes ./foo

(dlv) list

main.main() ./foo/cmd/kubectl/kubectl.go:28 (PC: 0x1a21080)
Command failed: open ./foo/cmd/kubectl/kubectl.go: no such file or directory

(dlv) config substitute-path -clear

(dlv) config substitute-path k8s.io/kubernetes .

(dlv) list

main.main() ./foo/cmd/kubectl/kubectl.go:28 (PC: 0x1a21080)
Command failed: open ./foo/cmd/kubectl/kubectl.go: no such file or directory

(dlv) config substitute-path
"k8s.io/kubernetes" → "."

I expected the -clear, followed by the correct  substitution to work, but it still is looking for "foo".

> 1. What version of Delve are you using (`dlv version`)?

$ dlv version
Delve Debugger
Version: 1.21.1
Build: $Id: a358c02f24aa7047ecc562b0587dc2d08330b2cf $

> 2. What version of Go are you using? (`go version`)?

$ go version
go version go1.21.3 linux/amd64

> 3. What operating system and processor architecture are you using?

Linux amd64