updates HEAP_SIZE to be configurable for embedded alloc #408

Job	Run time
Build SDK	1m 36s
Build SDK (nanos)	2m 16s
Build SDK (nanox)	2m 30s
Build SDK (nanosplus)	2m 16s
Build SDK (stax)	2m 23s
Run static analysis (nanos, include_gif)	1m 37s
Build SDK (flex)	2m 19s
Run static analysis (nanos, testmacro)	1m 14s
Run static analysis (nanos, ledger_secure_sdk_sys)	2m 3s
Run static analysis for cargo-ledger	1m 28s
Run static analysis (nanos, ledger_device_sdk)	2m 13s
Check code formatting	1m 9s
Run static analysis (nanox, include_gif)	1m 20s
Run static analysis (nanox, testmacro)	1m 15s
Run unit and integration tests (nanos)	2m 34s
Run static analysis (nanox, ledger_secure_sdk_sys)	1m 48s
Run unit and integration tests (nanox)	2m 35s
Run static analysis (nanox, ledger_device_sdk)	2m 14s
Run unit and integration tests (nanosplus)	2m 33s
Run unit and integration tests (stax)	2m 37s
Run static analysis (nanosplus, include_gif)	1m 27s
Run static analysis (nanosplus, testmacro)	1m 15s
Run unit and integration tests (flex)	2m 38s
Run static analysis (nanosplus, ledger_secure_sdk_sys)	1m 52s
Run static analysis (nanosplus, ledger_device_sdk)	2m 19s
Run static analysis (stax, include_gif)	1m 23s
Run static analysis (stax, testmacro)	1m 14s
Run static analysis (stax, ledger_secure_sdk_sys)	1m 59s
Run static analysis (stax, ledger_device_sdk)	2m 18s
Run static analysis (flex, include_gif)	1m 23s
Run static analysis (flex, testmacro)	1m 12s
Run static analysis (flex, ledger_secure_sdk_sys)	1m 59s
Run static analysis (flex, ledger_device_sdk)	2m 26s
	1h 3m 25s

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