[BOARD] add esp32s3-m5stack-stamps3 (#2088)

* [BOARD] add esp32s3-m5stack-stamps3

https://docs.m5stack.com/en/core/StampS3

* [BOARD] add esp32c3u-m5stamp

button long-press reset verified to work

* add build environments for addional M5Stack targets

esp32s3-m5stack-stamps3
esp32c3u-m5stamp

---------

Co-authored-by: Michael Haberler <git@mah.priv.at>

.github/workflows/build.yml

@@ -81,6 +81,8 @@ jobs:
           - "theengs-bridge-v11"
           - "theengs-plug"
           - "esp32dev-ble-broker"
+          - "esp32s3-m5stack-stamps3"
+          - "esp32c3u-m5stamp"
     runs-on: ubuntu-latest
     name: Build with PlatformIO
     steps: