Update version and fix tests (#336)

* Update version and fix tests

* update

* fix test

Update minor version (#334)

* Update minor version

* fix tests

* bump actions

* update jldoctest

* Update .github/workflows/documentation.yml

Co-authored-by: Raphael Saavedra <[email protected]>

* fix more docs

* fix another output from doctest

* fix docs

* fix exports

* update

* fix cross referencing

---------

Co-authored-by: Raphael Saavedra <[email protected]>

[Diff since v0.6.6](v0.6.6...v0.6.7)

**Closed issues:**
- Error with structural model and single precision (#195)
- Unobserved components model with smooth trend is broken (#317)

**Merged pull requests:**
- fix smooth trend (#319) (@guilhermebodin)

[Diff since v0.6.5](v0.6.5...v0.6.6)

**Closed issues:**
- max_q must be strictly positive? (auto arima) (#315)

**Merged pull requests:**
- Fix orders constraints (#316) (@guilhermebodin)

[Diff since v0.6.4](v0.6.4...v0.6.5)

**Merged pull requests:**
- fixed cholesky error in simulate (#314) (@dietzemarina)

[Diff since v0.6.3](v0.6.3...v0.6.4)

**Closed issues:**
- Example in the Quick Start not working (#311)

**Merged pull requests:**
- Fix `plotdiagnostics(kf)` (#312) (@guilhermebodin)

[Diff since v0.6.2](v0.6.2...v0.6.3)

**Closed issues:**
- simulate_scenarios for BasicStructuralExplanatory fails if seasonality is not 12 (#308)

**Merged pull requests:**
- Fix basic structural with exogenous variables simulation (#309) (@guilhermebodin)

[Diff since v0.6.1](v0.6.1...v0.6.2)

**Closed issues:**
- BasicStructuralExplanatory works ONLY for s = 12. (#306)

**Merged pull requests:**
- Fix Basic Structural Model with Explanatory (#307) (@guilhermebodin)

[Diff since v0.6.0](v0.6.0...v0.6.1)

**Closed issues:**
- Possible Issue with Std.Error in SARIMA() (#304)

**Merged pull requests:**
- Fix std err calculations (#305) (@guilhermebodin)

[Diff since v0.5.21](v0.5.21...v0.6.0)

**Closed issues:**
- Investigate hessian instability (#193)
- Allow Polynomials v2 in [compat] (#301)

**Merged pull requests:**
- Allow Polynomials v2 (#302) (@raphaelsaavedra)
- add some improvements (#303) (@guilhermebodin)