Cleanup python version properties

Now that python 2 is fully removed, there's no need for
version-specific properties. Remove them.

Also remove usages of embedded_launcher: true, as that
is the new default value.

Bug: 399954452
Test: Presubmits
Change-Id: I2acab763d3dfb01c9b423dd005e589ec0d0cd571

Author: Colecf

Diff for: scripts/Android.bp

@@ -74,9 +74,4 @@ python_test_host {
     test_options: {
         unit_test: true,
     },
-    version: {
-        py3: {
-            embedded_launcher: true,
-        },
-    },
 }

Diff for: tools/ninja_dependency_analysis/Android.bp

@@ -15,9 +15,4 @@ python_binary_host {
     proto: {
         canonical_path_from_root: false,
     },
-    version: {
-        py3: {
-            embedded_launcher: true,
-        },
-    }
 }

Diff for: vndk/tools/elfcheck/Android.bp

@@ -37,9 +37,4 @@ python_binary_host {
         "elfcheck/*.py",
         "fix_android_mk_prebuilt.py",
     ],
-    version: {
-        py3: {
-            embedded_launcher: true,
-        },
-    },
 }

Diff for: vndk/tools/header-checker/utils/Android.bp

@@ -25,10 +25,4 @@ python_binary_host {
         "create_reference_dumps.py",
         "utils.py",
     ],
-    version: {
-        py3: {
-            enabled: true,
-            embedded_launcher: true,
-        },
-    },
 }