Edsanche/431 add retention policy duration to powerplatform environment settings

[eduardodfmex]

This pull request introduces a new attribute, log_retention_period_in_days, to the environment settings data source, DTO, and models, along with corresponding test updates. The changes ensure that the retention period for audit logs can be optionally specified and computed.

Key changes include:

Schema and Models Updates:

• Added log_retention_period_in_days attribute to the EnvironmentSettingsDataSource schema in datasource_environment_settings.go.
• Added AuditRetentionPeriodV2 field to the environmentSettingsDto struct in dto.go.
• Updated AuditSettingsSourceModel to include log_retention_period_in_days in models.go.

Conversion Functions:

• Modified convertFromEnvironmentSettingsModel to handle AuditRetentionPeriodV2 in models.go.
• Updated convertFromEnvironmentSettingsDto to map AuditRetentionPeriodV2 to log_retention_period_in_days in models.go.

Test Updates:

• Added checks for log_retention_period_in_days in various test functions in datasource_environment_settings_test.go [1] and resource_environment_settings_test.go [2] [3] [4] [5] [6] [7].