Duplicating session_number in incremental materializations

[rjh336]

Describe the bug

There was an issue introduced in #73 in the updated segment_web_sessions model here where the comparison operator was flipped in the agg CTE for incremental materializations. The result is that session_number starts to get repeated for newly added sessions which we do not want.

Steps to reproduce

1. dbt run to MERGE to existing tables
2. check segment_web_sessions output and you will see new web sessions start counting from 1 instead of the last known session_number for each blended user ID

Expected results

session_number is incremented over a user's sessions

Actual results

duplicate session numbers for each user on incremental runs

Screenshots and log output

System information

The contents of your packages.yml file:

packages:
  - package: dbt-labs/segment
    version: 0.8.0
  - package: dbt-labs/audit_helper
    version: 0.5.0
  - package: dbt-labs/stitch_utils
    version: 0.4.1
  - package: dbt-labs/dbt_utils
    version: 0.8.0
  - package: dbt-labs/dbt_external_tables
    version: 0.8.0

Which database are you using dbt with?

• postgres
• redshift
• bigquery
• snowflake
• other (specify: ____________)

The output of dbt --version:

installed version: 1.0.3
   latest version: 1.0.3

Up to date!

Plugins:
  - bigquery: 1.0.0 - Up to date!
  - snowflake: 1.0.0 - Up to date!
  - redshift: 1.0.0 - Up to date!
  - postgres: 1.0.3 - Up to date!

The operating system you're using: MacOS

The output of python --version: Python 3.8.11

Additional context

Are you interested in contributing the fix?