…arate fields (open-telemetry#39762)

#### Description
- Breaks up values used in `datasource` parameter. Sends values to
receiver separately in order to process them separately.
- Datasource is still required (as before). However, if `datasource` is
not specified, the individual fields are used.
- Allows for encryption, character escaping, and driver-specific
processing of these fields.

#### Link to tracking issue

Fixes
open-telemetry#39760

#### Testing
- Unit tests:
    - scraper_test.go
    - config_test.go
    - receiver_test.go
- Testing locally:
    - Set up agent with sqlreceiver running
    - Use this configuration:
    ```receivers:
            sqlquery:
              driver: postgres
              host: localhost
              port: 5432
              username: justinvoss
              database: bindplane18
              additional_params:
                sslmode: disable
              storage: file_storage
              queries:
                - sql: "select * from resources"
                  tracking_start_value: "10000"
                  logs:
                    - body_column: name
     ```
- Using the old configuration should still work too:
   ```receivers:
          sqlquery:
datasource:
postgresql://justinvoss@localhost:5432/bindplane18?sslmode=disable
              driver: postgres
              queries:
                  - logs:
                      - attribute_columns:
                          - name
                          - kind
                      - body_column: data
                    sql: select * from resources```
                   
   
#### Documentation
- Update README.md