Add tests for alpha BT values

- Update deps
- Update release notes for v3.1

src/Tests.CSharp/PostgresCSharpTests.cs

@@ -549,7 +549,7 @@ public static class PostgresCSharpTests
                 var theCount = await Count.All(PostgresDb.TableName);
                 Expect.equal(theCount, 5, "There should have been 5 matching documents");
             }),
-            TestCase("ByField succeeds", async () =>
+            TestCase("ByField succeeds for numeric range", async () =>
             {
                 await using var db = PostgresDb.BuildDb();
                 await LoadDocs();
@@ -557,6 +557,14 @@ public static class PostgresCSharpTests
                 var theCount = await Count.ByField(PostgresDb.TableName, Field.BT("NumValue", 10, 20));
                 Expect.equal(theCount, 3, "There should have been 3 matching documents");
             }),
+            TestCase("ByField succeeds for non-numeric range", async () =>
+            {
+                await using var db = PostgresDb.BuildDb();
+                await LoadDocs();
+
+                var theCount = await Count.ByField(PostgresDb.TableName, Field.BT("Value", "aardvark", "apple"));
+                Expect.equal(theCount, 1, "There should have been 1 matching document");
+            }),
             TestCase("ByContains succeeds", async () =>
             {
                 await using var db = PostgresDb.BuildDb();