fix: use explicit caret for pyshifty's 0.2.x pin

A bare two-component version string ("0.2") is parsed by Poetry as an exact
match (==0.2, i.e. only 0.2.0), not a caret range -- unlike a three-component
string, which gets caret treatment automatically. Write the caret explicitly
(^0.2) so any 0.2.x release is actually accepted. Re-locks to the latest
matching release, 0.2.6.

Author: gtfierro

poetry.lock

@@ -41,7 +41,7 @@ brick-tq-shacl = {optional = true, version="0.3.4a2"}
 # SHACL engine and the algebraic validation/repair path are always available.
 # Pinned to the 0.2.x line -- the algebra/repair API is not yet stable across
 # minor releases.
-pyshifty = "0.2"
+pyshifty = "^0.2"
 werkzeug="^2.3.7"
 types-jsonschema = "^4.21.0.20240311"
 matplotlib = "^3.9.2"