Add release/5.4 branch support to common.py

Author: shahmishal

common.py

@@ -46,6 +46,21 @@
         'yams': '3.0.1',
         'swift-tools-support-core': 'main',
     },
+    'release/5.4': {
+        'llvm-project': 'swift/release/5.4',
+        'swift': 'release/5.4',
+        'cmark': 'release/5.4',
+        'ninja': 'release',
+        'llbuild': 'release/5.4',
+        'swiftpm': 'main',
+        'swift-corelibs-libdispatch': 'release/5.4',
+        'swift-corelibs-foundation': 'release/5.4',
+        'swift-corelibs-xctest': 'release/5.4',
+        'swift-argument-parser': '0.3.0',
+        'swift-driver': 'main',
+        'yams': '3.0.1',
+        'swift-tools-support-core': 'main',
+    },
     'release/5.3': {
         'llvm-project': 'swift/release/5.3',
         'swift': 'release/5.3',