minor fixes to splines example (#367)

* create truncated regression example

* delete truncated regression example from main branch

* create truncated regression example

* delete truncated regression example from main branch

* create truncated regression example

* delete truncated regression example from main branch

* fix incorrect statement about pm.NormalMixture

* PyMC3 -> PyMC in title. Remove pymc.* tags

* update front matter

* correct front matter / authorship

Co-authored-by: Benjamin T. Vincent <drbenvincent@users.noreply.github.com>

Author: Benjamin T. Vincent

examples/case_studies/spline.ipynb

@@ -6,17 +6,18 @@ jupytext:
     format_version: 0.13
     jupytext_version: 1.13.7
 kernelspec:
-  display_name: Python 3.9.10 ('pymc-dev-py39')
+  display_name: Python 3.10.4 ('pymc_env')
   language: python
   name: python3
 ---
 
-# Splines in PyMC3
+(spline)=
+# Splines
 
-:::{post} May 6, 2022 
-:tags: patsy, pymc.Deterministic, pymc.Exponential, pymc.Model, pymc.Normal, regression, spline
+:::{post} June 4, 2022 
+:tags: patsy, regression, spline
 :category: beginner
-:author: Joshua Cook updated by Tyler James Burch, Chris Fonnesbeck
+:author: Joshua Cook
 :::
 
 +++ {"tags": []}
@@ -275,6 +276,14 @@ plt.fill_between(
 
 +++
 
+## Authors
+
+- Created by Joshua Cook
+- Updated by Tyler James Burch
+- Updated by Chris Fonnesbeck
+
++++
+
 ## Watermark
 
 ```{code-cell} ipython3