Migrate to RTIC 0.6 (alpha)

Refactor for RTIC 0.6.
Change tasks priorities as this is most certainly the underlying problem.
Party drop support for bme680 crate, only use drogue's crate now.

Cargo.toml

@@ -47,7 +47,9 @@ smart-leds = "0.3"
 ## Waiting for next release with 2in13 support
 epd-waveshare = {git = "https://github.com/caemor/epd-waveshare.git", rev="87e63741ef9335439d97f587a781630077be2515" }
 embedded-graphics = "0.6"
-cortex-m-rtic = "0.5"
+cortex-m-rtic = "0.6.0-alpha.0"
+rtic-core = "0.3"
+
 bme680 = { version = "0.5", optional = true }
 
 drogue-bme680 = { optional = true, git = "https://github.com/dkm/drogue-bme680.git", branch = "main" }