Fix C with Cedilla GSM code point (#318)

* Fix C with Cedilla GSM code point

EncodingDetector incorrectly uses the lowercase version of `Latin Small Letter C with Cedilla (U+00E7)` instead of `Latin Capital Letter C with Cedilla (U+00C7)`.

See https://en.wikipedia.org/wiki/GSM_03.38#GSM_7-bit_default_alphabet_and_extension_table_of_3GPP_TS_23.038_/_GSM_03.38

* Fix Tests for French C cedillia

* Fix frenchWithOnlyGSM test characters

Co-authored-by: Starfox64 <louisdijon21@yahoo.fr>

Author: Starfox64

src/Message/EncodingDetector.php

@@ -29,7 +29,7 @@ public function requiresUnicodeEncoding($content): bool
         $gsmCodePoints = array_map(
             $this->convertIntoUnicode(),
             [
-                '@', '£', '$', '¥', 'è', 'é', 'ù', 'ì', 'ò', 'ç', "\r", 'Ø', 'ø', "\n", 'Å', 'å',
+                '@', '£', '$', '¥', 'è', 'é', 'ù', 'ì', 'ò', 'Ç', "\r", 'Ø', 'ø', "\n", 'Å', 'å',
                 'Δ', '_', 'Φ', 'Γ', 'Λ', 'Ω', 'Π', 'Ψ', 'Σ', 'Θ', 'Ξ', 'Æ', 'æ', 'ß', 'É',
                 ' ', '!', '"', '#', '¤', '%', '&', '\'', '(', ')', '*', '+', ',', '-', '.', '/',
                 '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ':', ';', '<', '=', '>', '?',

test/Message/EncodingDetectorTest.php

@@ -49,9 +49,13 @@ public function unicodeProvider(): array
             'près du mälström où brûlent les novæ.',
             true
         ];
-        $r['frenchWithOnlyGSM'] = [
+        $r['frenchWithUnicode2'] = [
             'j\'étais donc plein de songes ! L\'espérance en chantant me berçait de mensonges. J\'étais ' .
             'donc cet enfant, hélas !',
+            true
+        ];
+        $r['frenchWithOnlyGSM'] = [
+            'Le progrès est le moteur de la science ; l\'idéal est le générateur de l\'art.',
             false
         ];
         $r['icelandic'] = ['Kæmi ný öxi hér ykist þjófum nú bæði víl og ádrepa ', true];