DxCore is not shown in the board manager

[sstaub]

Describe the bug
The board manager does not show the cores from SpenceKonde
[https://github.com/SpenceKonde]
There are the DxCore and some Tiny cores.
The board manager works in the standard Arduino IDE 1.8.13

To Reproduce
Steps to reproduce the behavior:

1. add http://drazzy.com/package_drazzy.com_index.json to CLI config
2. restart the IDE I get many error messages when loading, see issue v 0.1.0 problems with 3rd party cores (MegaCoreX) #306
3. The cores are not seen in the board manager

Expected behavior
The core should also work with the Pro IDE

Desktop (please complete the following information):

• OS: macOS Catalina
• Version 0.1.0

[kittaakos]

From here:

rror while updating index in attempt 8: Error: 2 UNKNOWN: invalid package index in http://drazzy.com/package_drazzy.com_index.json: invalid patch version separator 'a'[INFO] Updating index [url: https://downloads.arduino.cc/packages/package_index.json]
Updating index: package_index.json completed.
Updating index: package_index.json.sig completed.
[INFO] Checking signature [error: opening signature file: open /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/055000167.sig: no such file or directory, index: /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/055000167, signaturefile: /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/055000167.sig]
[INFO] Updating index [url: https://github.com/stm32duino/BoardManagerFiles/raw/master/STM32/package_stm_index.json]
Updating index: package_stm_index.json completed.
[INFO] Checking signature [error: opening signature file: open /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/293532465.sig: no such file or directory, index: /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/293532465, signaturefile: /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/293532465.sig]
[INFO] Updating index [url: https://mcudude.github.io/MegaCoreX/package_MCUdude_MegaCoreX_index.json]
Updating index: package_MCUdude_MegaCoreX_index.json completed.
[INFO] Checking signature [error: opening signature file: open /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/703650524.sig: no such file or directory, index: /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/703650524, signaturefile: /var/folders/vd/yv1mb7lx6gn7ymffgtjk6hx80000gn/T/703650524.sig]
[INFO] Updating index [url: http://drazzy.com/package_drazzy.com_index.json]
Updating index: package_drazzy.com_index.json completed.

[per1234]

Thanks so much for bringing this to everyone's attention @sstaub!

Since the code that causes this is in Arduino CLI, I'm going to close it in favor of the report of the same issue in the arduino/arduino-cli repository: arduino/arduino-cli#920. Feel free to subscribe to that issue to follow the discussion and provide any feedback you might have.