Do not send msg3 if key confirm fails in PASE

[pan-apple]

Problem

PASE Session state machine is sending Msg3 even if KeyConfirm fails. It later sends the error message as well.
It should send Msg3 only after all the checks are complete.

Change overview

Move the code to send Msg3 after KeyConfirm.

Testing

Added a unit test to trigger condition where KeyConfirm would fail.
Manually tested the flow using Python controller, chip-tool controller, and iOS CHIPTool apps.

[pan-apple]

rebased

[github-actions]

Size increase report for "esp32-example-build" from 1f1b715

File	Section	File	VM
chip-all-clusters-app.elf	.flash.text	-32	-32

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-all-clusters-app.elf and ./pull_artifact/chip-all-clusters-app.elf:

sections,vmsize,filesize
.debug_loc,0,134
.debug_info,0,18
.debug_line,0,14
.debug_str,0,-2
.flash.text,-32,-32

Comparing ./master_artifact/chip-pigweed-app.elf and ./pull_artifact/chip-pigweed-app.elf:

sections,vmsize,filesize