Selecting partitions can crash installer

[13r0ck]

Distribution (run cat /etc/os-release):

NAME="Pop!_OS"
VERSION="21.10"
ID=pop
ID_LIKE="ubuntu debian"
PRETTY_NAME="Pop!_OS 21.10"
VERSION_ID="21.10"
HOME_URL="https://pop.system76.com"
SUPPORT_URL="https://support.system76.com"
BUG_REPORT_URL="https://github.com/pop-os/pop/issues"
PRIVACY_POLICY_URL="https://system76.com/privacy"
VERSION_CODENAME=impish
UBUNTU_CODENAME=impish
LOGO=distributor-logo-pop-os

Related Application and/or Package Version (run apt policy $PACKAGE NAME):

distinst:
  Installed: 0.3.2~1642534021~21.10~ebc554a
  Candidate: 0.3.2~1642534021~21.10~ebc554a
  Version table:
 *** 0.3.2~1642534021~21.10~ebc554a 1001
       1001 http://apt.pop-os.org/release impish/main amd64 Packages
        100 /var/lib/dpkg/status

Issue/Bug Description:
If doing a custom install and partitions are selected without formatting, the installer will crash without displaying the error.

Steps to reproduce (if you know):

crash.mp4

Expected behavior:
Installer shouldn't crash

Other Notes: