[bug]: PSBT funding for SIMPLE_TAPROOT channels returns inconsistent funding address

[alexbosworth]

Background

When using the PSBT shim in the OpenChannel API, an invalid address is returned for the funding address. Because these are inconsistent, sending to one would suggest chain funds potentially getting stuck

Your environment

• lnd v0.17.0 RC1

Steps to reproduce

• Use the OpenChannel API with the PSBT shim
• Look at the result of psbt_fund which will return funding_address and psbt

Expected behavior

• The funding_address and psbt internally should reflect an identical address to fund for the channel
• This address should be a P2TR address

Actual behavior

• funding_address returns a V0 segwit address
• psbt contains a V1 P2TR address

Example output:

• funding_address: bcrt1q0dz5fktjdemgf04nvla3fxdcye5pwuk5pt0wznudc0mmvrcr4c3q5m7g7h
• psbt: cHNidP8BADUCAAAAAAFAQg8AAAAAACJRIB3p6kApstllpoGVEYAa6VuHM/H8bqdQa7gm+D4+ac8TAAAAAAAA

[guggero]

Found the issue, working on a fix.