update CQL example notebook with latest CQL2 syntax

[philvarner]

Related Issue(s): #150

Description:

Update CQL2 example notebook to use prod planetary computer and use current CQL2 JSON syntax

PR Checklist:

• Code is formatted
• Tests pass
• Changes are added to the CHANGELOG

[codecov-commenter]

Codecov Report

Merging #170 (2fde68a) into main (0b310f0) will decrease coverage by 0.01%.
The diff coverage is 92.30%.

@@            Coverage Diff             @@
##             main     #170      +/-   ##
==========================================
- Coverage   81.20%   81.19%   -0.02%     
==========================================
  Files           9        9              
  Lines         564      569       +5     
==========================================
+ Hits          458      462       +4     
- Misses        106      107       +1     

Impacted Files	Coverage Δ
pystac_client/item_search.py	88.35% <91.66%> (-0.18%)	⬇️
pystac_client/client.py	79.36% <100.00%> (ø)

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[gadomski]

Needs some additional docs dependencies, here's what I used:

diff --git a/requirements-docs.txt b/requirements-docs.txt
index 25cc64c..bbe3d2d 100644
--- a/requirements-docs.txt
+++ b/requirements-docs.txt
@@ -1,6 +1,8 @@
 ipykernel~=6.2
 ipython~=7.27
 Sphinx~=4.1
+geopandas~=0.10.2
+hvplot~=0.8.0
 sphinxcontrib-fulltoc~=1.2
 myst-parser~=0.15.2
 nbsphinx~=0.8

[philvarner]

@gadomski great, thanks -- I had to add them to run it locally too, but I just assumed I wasn't following the setup documentation or something