async-flow bijection is not always symmetric

[mhofman]

Describe the bug

The addition of async-flow endowments in #9566 caused the bijection to not always be symmetrical: both the unwrapped version and the original guest are registered. This resulted in some equate(g, h) calls to fail.

More details in #9736

To Reproduce

See failing test

agoric-sdk/packages/boot/test/orchestration/contract-upgrade.test.ts

Lines 59 to 68 in e5f1d9b

	Error#2 ERROR_NOTE: Caused by (Error#3)
	Error#3: internal h->g: Object [Alleged: findBrandInVBank] {} -> Object [Alleged: findBrandInVBank guest wrapper] {
	__getInterfaceGuard__: [Function: In "__getInterfaceGuard__" method of (findBrandInVBank)],
	__getMethodNames__: [Function: __getMethodNames__],
	apply: [Function: In "apply" method of (findBrandInVBank)]
	} vs [Function: unwrapped]
	at makeError (file:///opt/agoric/agoric-sdk/node_modules/ses/src/error/assert.js:347:61)
	at fail (file:///opt/agoric/agoric-sdk/node_modules/ses/src/error/assert.js:479:20)
	at Fail (file:///opt/agoric/agoric-sdk/node_modules/ses/src/error/assert.js:489:39)
	at Object.has (.../async-flow/src/bijection.js:177:6)

part of #9719

Expected behavior

Endowments should work through the async flow membrane back and forth, even for wrapped ones

Testing concerns

Needs to add sufficient test coverage of these cases