GH-1357: parse Flight SQL JDBC boolean properties case-insensitively (#1358)

## What's Changed

`ArrowFlightConnectionProperty.getBoolean` only treated `1` and the
exact lowercase `true` as true, and connection-string values are not
normalized, so `useEncryption=TRUE` (or `True`) parsed as false. Since
`useEncryption` defaults to true and drives `withEncryption`, that
silently downgraded the connection to plaintext and sent the auth
handshake and credentials in the clear. This compares `true`
case-insensitively while still honoring `1`, matching how JDBC drivers
normally parse boolean options.

Closes #1357.

Author: Arawoof06

flight/flight-sql-jdbc-core/src/main/java/org/apache/arrow/driver/jdbc/utils/ArrowFlightConnectionConfigImpl.java

@@ -333,7 +333,7 @@ public Object get(final Properties properties) {
      */
     public Boolean getBoolean(final Properties properties) {
       final String valueFromProperties = String.valueOf(get(properties));
-      return valueFromProperties.equals("1") || valueFromProperties.equals("true");
+      return valueFromProperties.equals("1") || valueFromProperties.equalsIgnoreCase("true");
     }
 
     /**

flight/flight-sql-jdbc-core/src/test/java/org/apache/arrow/driver/jdbc/utils/ArrowFlightConnectionConfigImplTest.java

@@ -39,6 +39,7 @@
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.jupiter.params.provider.ValueSource;
 
 public final class ArrowFlightConnectionConfigImplTest {
 
@@ -71,6 +72,22 @@ public void testGetProperty(
         arrowFlightConnectionConfigFunction.apply(arrowFlightConnectionConfig), is(expected));
   }
 
+  @ParameterizedTest
+  @ValueSource(strings = {"true", "TRUE", "True", "tRuE", "1"})
+  public void testUseEncryptionAcceptsTruthyValuesCaseInsensitively(String value) {
+    // A connection string value like "TRUE" must enable TLS. Parsing it as false would
+    // silently downgrade the connection to plaintext and leak credentials.
+    properties.put(USE_ENCRYPTION.camelName(), value);
+    assertThat(arrowFlightConnectionConfig.useEncryption(), is(true));
+  }
+
+  @ParameterizedTest
+  @ValueSource(strings = {"false", "FALSE", "0", ""})
+  public void testUseEncryptionRejectsFalsyValues(String value) {
+    properties.put(USE_ENCRYPTION.camelName(), value);
+    assertThat(arrowFlightConnectionConfig.useEncryption(), is(false));
+  }
+
   public static Stream<Arguments> provideParameters() {
     int port = RANDOM.nextInt(Short.toUnsignedInt(Short.MAX_VALUE));
     boolean useEncryption = RANDOM.nextBoolean();