all: gofmt -w -r 'interface{} -> any' src

And then revert the bootstrap cmd directories and certain testdata.
And adjust tests as needed.

Not reverting the changes in std that are bootstrapped,
because some of those changes would appear in API docs,
and we want to use any consistently.
Instead, rewrite 'any' to 'interface{}' in cmd/dist for those directories
when preparing the bootstrap copy.

A few files changed as a result of running gofmt -w
not because of interface{} -> any but because they
hadn't been updated for the new //go:build lines.

Fixes #49884.

Change-Id: Ie8045cba995f65bd79c694ec77a1b3d1fe01bb09
Reviewed-on: https://go-review.googlesource.com/c/go/+/368254
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>

handshake_client_test.go

@@ -134,7 +134,7 @@ type clientTest struct {
 	cert []byte
 	// key, if not nil, contains either a *rsa.PrivateKey, ed25519.PrivateKey or
 	// *ecdsa.PrivateKey which is the private key for the reference server.
-	key interface{}
+	key any
 	// extensions, if not nil, contains a list of extension data to be returned
 	// from the ServerHello. The data should be in standard TLS format with
 	// a 2-byte uint16 type, 2-byte data length, followed by the extension data.
@@ -171,7 +171,7 @@ func (test *clientTest) connFromCommand() (conn *recordingConn, child *exec.Cmd,
 	certPath := tempFile(string(cert))
 	defer os.Remove(certPath)
 
-	var key interface{} = testRSAPrivateKey
+	var key any = testRSAPrivateKey
 	if test.key != nil {
 		key = test.key
 	}