Don't exit doc preparation even if changelog is empty for any provider

[amoghrajesh]

@eladkal found an edge case where if any provider doesn't have a changelog to process, the process of breeze release-management generate-issue-content-providers exits and doesn't continue ahead.

How was this tested?

1. Cleared the changelog entirely for standard provider to ensure it has no PRs to process
2. Ran the breeze release-management generate-issue-content-providers command before changes:

Skipping extracting PRs for provider qdrant as it is missing in dist
Skipping extracting PRs for provider redis as it is missing in dist
Skipping extracting PRs for provider salesforce as it is missing in dist
Skipping extracting PRs for provider samba as it is missing in dist
Skipping extracting PRs for provider segment as it is missing in dist
Skipping extracting PRs for provider sendgrid as it is missing in dist
Skipping extracting PRs for provider sftp as it is missing in dist
Skipping extracting PRs for provider singularity as it is missing in dist
Extracting PRs for provider slack
Extracting PRs for provider smtp
Extracting PRs for provider snowflake
Extracting PRs for provider sqlite
Skipping extracting PRs for provider ssh as it is missing in dist
Extracting PRs for provider standard
Skipping provider standard. The changelog file doesn't contain any PRs for the release.

3. Ran the same command after the changes:

Extracting PRs for provider smtp
Extracting PRs for provider snowflake
Extracting PRs for provider sqlite
Extracting PRs for provider ssh
Extracting PRs for provider standard
I AM HERE for standard
Skipping provider standard. The changelog file doesn't contain any PRs for the release.

Extracting PRs for provider tableau
Extracting PRs for provider telegram
Extracting PRs for provider teradata
Extracting PRs for provider trino
Extracting PRs for provider vertica
Extracting PRs for provider weaviate
Extracting PRs for provider yandex

---

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[eladkal]

Thanks!

[potiuk]

Hmm... there seem to be error generated by that however (see failing tests) - looks like it expects to have provider in the dictionary and it does not find it.