Supported driver architectures

[adespawn]

❓ Not related to this PR, but does Rust Driver support all these architectures?
🌱 If some of them not, then let's remove them from here not to confuse users / give them false hope.

Originally posted by @wprzytula in #291 (comment)

[adespawn]

Desired architechtures for GA: Macos arm + x64 + linux arm (on top of the already supported linux x64)

[adespawn]

@wprzytula / @dkropachev
Do you know of any github actions, that run ccm on an arm machine?

[adespawn]

I've managed the following, in regards of this issue:

• Testing the linux arm architecture through examples
• Testing the macos (x64 only for now - no attempts of arm yet) through integration tests with ccm (Cassandra only).

After internal discussion we settled on the following addition to the CI:

• add extended CI, which will be run manually before the releases
• run example with single node version with arm linux on each PR
• run all supported node versions with arm linux as part of the extended CI
• run macos integration tests on each PR
• if CCM timeouts #244 bites us on macOS move those integration tests to extended CI only
• add other node versions to the integration tests as part of extended CI

[wprzytula]

I've managed the following, in regards of this issue:

• Testing the linux arm architecture through examples
• Testing the macos (x64 only for now - no attempts of arm yet) through integration tests with ccm (Cassandra only).

After internal discussion we settled on the following addition to the CI:

• add extended CI, which will be run manually before the releases
• run example with single node version with arm linux on each PR
• run all supported node versions with arm linux as part of the extended CI
• run macos integration tests on each PR
• if CCM timeouts #244 bites us on macOS move those integration tests to extended CI only
• add other node versions to the integration tests as part of extended CI

Could you create a (markdown) table that will help visualise this strategy?