clickhouse / string type cast fix

[emreyalvac]

Description:
Change Clickhouse string type cast function of insert flow.

Before this fix (check http.status_code):
{'http.method': 'GET', 'http.scheme': 'http', 'http.target': '/hc', 'http.url': 'url', 'http.flavor': '1.1', 'http.user_agent': 'Envoy/HC', 'http.status_code': '', 'net.host.name': 'url'}

After this fix (check http.status_code)::
{'http.method': 'GET', 'http.scheme': 'http', 'http.target': '/hc', 'http.url': 'url', 'http.flavor': '1.1', 'http.user_agent': 'Envoy/HC', 'http.status_code': '200', 'net.host.name': 'url'}

[linux-foundation-easycla]

• ✅ login: emreyalvac / name: Emre (e6c7db1)
• ❌ The commit (dfb9cd0, fe12f63). This user is missing the User's ID, preventing the EasyCLA check. Consult GitHub Help to resolve.For further assistance with EasyCLA, please submit a support request ticket.

[hanjm]

Thanks. LGTM, Please add a changelog entry https://github.com/open-telemetry/opentelemetry-collector/blob/main/CONTRIBUTING.md#adding-a-changelog-entry

[emreyalvac]

@hanjm can u review?

thanks.

[hanjm]

@emreyalvac , seems CLA check not pass, please check your git config user.email is same as your github settings, then sign the CLA.

$ git config -l|grep user

[emreyalvac]

#17834