version bumps for `v0.5.0`

[GitGab19]

Similar to #359

[plebhash]

#495 is bumping:

• stratum-apps: 0.4.0 -> 0.5.0
• bitcoin_core_sv2: 0.2.0 -> 0.3.0
• pool_sv2: 0.3.0 -> 0.4.0
• jd_server_sv2: 0.2.0 -> 0.3.0
• jd_client_sv2:0.2.0 -> 0.3.0
• translator_sv2: 0.2.5 -> 0.3.0
• integration_tests_sv2: 0.2.0 -> 0.3.0