SCons: Ensure written files are properly flushed/closed

This broke at least the generation of AndroidManifest.xml with Python 3.13.1.

methods.py

@@ -43,6 +43,7 @@ def build_shader_header(target, source, env):
             line = fs.readline()
 
         fd.write(";\n")
+        fd.close()
 
     return 0
 
@@ -1105,6 +1106,7 @@ def update_version():
     f.write("#define VERSION_STATUS " + str(version.status) + "\n")
     import datetime
     f.write("#define VERSION_YEAR " + str(datetime.datetime.now().year) + "\n")
+    f.close()
 
 
 def parse_cg_file(fname, uniforms, sizes, conditionals):
@@ -1175,6 +1177,7 @@ def build_cg_shader(sname):
         fd.write('\t\tVP_%s,\n' % vp_uniforms[i].upper())
 
     fd.write("\t};\n")
+    fd.close()
 
 
 import glob
@@ -1230,6 +1233,7 @@ void unregister_module_types() {
 
     f = open("modules/register_module_types.gen.cpp", "w")
     f.write(modules_cpp)
+    f.close()
 
     return module_list
 
@@ -1464,6 +1468,7 @@ def save_active_platforms(apnames, ap):
         wf = x + "/logo.gen.h"
         logow = open(wf, "w")
         logow.write(str)
+        logow.close()
 
 
 def no_verbose(sys, env):