ci: coverage: generate HTML coverage

[mniestroj]

This generates HTML coverage from all native_sim runs:

• both 32-bit and 64-bit
• samples and tests

[github-actions]

Visit the preview URL for this PR (updated for commit c594428):

https://golioth-firmware-sdk-doxygen-dev--pr607-coverage-html-jtm2wihp.web.app

_{(expires Thu, 26 Sep 2024 11:26:35 GMT)}

_{🔥 via Firebase Hosting GitHub Action 🌎}

_{Sign: a9993e61697a3983f3479e468bcb0b616f9a0578}

[github-actions]

Code Coverage (Linux)

Type	Coverage
lines	65.6% (1402 of 2138 lines)
functions	78.1% (139 of 178 functions)

[github-actions]

Code Coverage (Zephyr)

Package	Line Rate	Branch Rate	Health
examples.zephyr.certificate_provisioning.src	77%	59%	✔
examples.zephyr.common	36%	16%	❌
examples.zephyr.common.include.samples.common	100%	100%	✔
examples.zephyr.fw_update.src	0%	0%	❌
examples.zephyr.hello.src	100%	50%	✔
examples.zephyr.lightdb.delete.src	87%	50%	✔
examples.zephyr.lightdb.get.src	90%	55%	✔
examples.zephyr.lightdb.observe.src	86%	50%	✔
examples.zephyr.lightdb.set.src	79%	50%	✔
examples.zephyr.logging.src	100%	50%	✔
examples.zephyr.rpc.src	88%	62%	✔
examples.zephyr.settings.src	96%	50%	✔
examples.zephyr.stream.src	74%	62%	➖
include.golioth	75%	50%	✔
port.zephyr	49%	14%	❌
src	67%	27%	➖
tests.hil.platform.zephyr.src	100%	100%	✔
tests.hil.tests.connection	93%	55%	✔
tests.hil.tests.lightdb	98%	46%	✔
tests.hil.tests.ota	93%	42%	✔
tests.hil.tests.rpc	88%	41%	✔
tests.hil.tests.settings	100%	57%	✔
tests.hil.tests.stream	82%	32%	✔
Summary	70% (2768 / 3956)	30% (1168 / 3875)	➖