py-flask-sqlalchemy: add v2.5.1 (spack#34999)

* Fix py-parsl specification

* Add older version of py-flask-sqlalchemy

var/spack/repos/builtin/packages/py-flask-sqlalchemy/package.py

@@ -18,10 +18,19 @@ class PyFlaskSqlalchemy(PythonPackage):
 
     license("BSD-3-Clause")
 
+    # If [email protected]: is too restrictive, consider downgrading py-flask-sqlalchemy to @2.
     version("3.0.2", sha256="16199f5b3ddfb69e0df2f52ae4c76aedbfec823462349dabb21a1b2e0a2b65e9")
-
-    # https://github.com/pallets-eco/flask-sqlalchemy/blob/3.0.2/pyproject.toml
-    depends_on("[email protected]:", type=("build", "run"))
-    depends_on("[email protected]:", type=("build", "run"))
-    depends_on("[email protected]:", type=("build", "run"))
-    depends_on("py-pdm-pep517@1:", type="build")
+    version("2.5.1", sha256="2bda44b43e7cacb15d4e05ff3cc1f8bc97936cc464623424102bfc2c35e95912")
+
+    with when("@3"):
+        # https://github.com/pallets-eco/flask-sqlalchemy/blob/3.0.2/pyproject.toml
+        depends_on("[email protected]:", type=("build", "run"))
+        depends_on("[email protected]:", type=("build", "run"))
+        depends_on("[email protected]:", type=("build", "run"))
+        depends_on("py-pdm-pep517@1:", type="build")
+
+    with when("@2"):
+        # https://github.com/pallets-eco/flask-sqlalchemy/blob/2.5.1/setup.py
+        depends_on("[email protected]:", type=("build", "run"))
+        depends_on("[email protected]:", type=("build", "run"))
+        depends_on("py-setuptools", type="build")