#3371 imm: immxml-merge fails when merging XML files with different encodings in Python 2

[Nguyen Huynh Tai]

In python2, the immxml-merge tool uses the encoding of the first input file to set the output file's encoding. If any subsequent input files require UTF-8 encoding but the first file is not encoded in UTF-8, immxml-merge will fail.

encoding in first source xml document: None
Traceback (most recent call last):
  File "./src/imm/tools/immxml-merge", line 627, in <module>
    main(sys.argv[1:])
  File "./src/imm/tools/immxml-merge", line 619, in main
    merged_doc.save_result()
  File "./src/imm/tools/immxml-merge", line 389, in save_result
    file_object.write(string + "\n")
UnicodeEncodeError: 'ascii' codec can't encode character u'\xc5' in position 229: ordinal not in range(128)

[Nguyen Huynh Tai]

commit c035b53056d1cce502a4fea40d5d48e6770df73e (HEAD -> develop, origin/develop)
Author: tai.h.nguyen <tai.h.nguyen@endava.com>
Date:   Mon Apr 28 17:57:18 2025 +0700

    imm: Fix immxml-merge failure caused by encoding mismatch [#3371]

    The immxml-merge tool uses the encoding of the first input file to set the
    output file's encoding. If any subsequent input files require UTF-8 encoding
    but the first file is not encoded in UTF-8, then immxml-merge will fail.

    UTF-8 encoding will be applied to the output files if any input file
    uses UTF-8 encoding.