[OOB] Upgrades 'dotnet-core' to '4.2.19'

[SvcGitHubPATagentoperatorimages]

Automated OOB update requested by SvcGitHubPATagentoperatorimages.

Agent: dotnet-core
Version: 4.2.18 -> 4.2.19

[github-actions]

Images built:

dotnet-core: ghcr.io/contrast-security-oss/agent-operator-images/agent-dotnet-core@sha256:2dbd4d41eb3bc18af085f364b4e6ce31f3aa7833929ceb407272f6fb9e4da1db
dotnet-framework: ghcr.io/contrast-security-oss/agent-operator-images/agent-dotnet-framework@sha256:ef85bbf7362ab410ce686962c3134060b1ef02a7faa92520b71bbac354e01b0f
java: ghcr.io/contrast-security-oss/agent-operator-images/agent-java@sha256:40160811edd202d2a2b2f8ffe31c96cf4876320d99cd92f3dd80de6f3b4171b8
nodejs: ghcr.io/contrast-security-oss/agent-operator-images/agent-nodejs@sha256:02ccde3f4175b7486707b2cee331705253a3ec208113a21433814db36975a0be
php: ghcr.io/contrast-security-oss/agent-operator-images/agent-php@sha256:ad1b00c48380491e04650402dc0d30717a8cf549af8cc570779df19f23e643f8
python: ghcr.io/contrast-security-oss/agent-operator-images/agent-python@sha256:40f1f2ca142ec9be6a96b680843b66e7de1b9f9cb569fac54ee6cb94d8c2c4d8