do not add extra newline in RECORD

acceptance/cmd/patchwhl/output.txt

@@ -17,7 +17,7 @@ Warn: Patched whl: my_test_code-0.0.1-py3-none-any.whl -> my_test_code-0.0.1+202
  Home-page: https://databricks.com
 --- original/my_test_code-0.0.1+2025030514073312.dist-info/RECORD
 +++ output/my_test_code-0.0.1+2025030514073312.dist-info/RECORD
-@@ -1,7 +1,8 @@
+@@ -1,7 +1,7 @@
  src/__init__.py,sha256=BRmKeYehopKv4NG_SFa7t6wn248RrPHJivu7DM1R-Rw,48
  src/__main__.py,sha256=8TtsnLsaJEM35Y4L8ocrv-qfxusgYpRL2HPyYiabHng,242
 -my_test_code-0.0.1.dist-info/METADATA,sha256=6fyVq4hexXGUP_J2mB1CI-ijZ6CenvKNIlHx0bKPRJ0,197
@@ -30,4 +30,3 @@ Warn: Patched whl: my_test_code-0.0.1-py3-none-any.whl -> my_test_code-0.0.1+202
 +my_test_code-0.0.1+2025030514073312.dist-info/entry_points.txt,sha256=oDWOW9SsBlk4Uejj1ftYPBxfhJ5ZJctb4JOUIG1rc-4,34
 +my_test_code-0.0.1+2025030514073312.dist-info/top_level.txt,sha256=74rtVfumQlgAPzR5_2CgYN24MB0XARCg0t-gzk6gTrM,4
 +my_test_code-0.0.1+2025030514073312.dist-info/RECORD,,
-+

acceptance/cmd/patchwhl/output/my_test_code-0.0.1+2025030514073312.dist-info/RECORD

@@ -5,4 +5,3 @@ my_test_code-0.0.1+2025030514073312.dist-info/WHEEL,sha256=oiQVh_5PnQM0E3gPdiz09
 my_test_code-0.0.1+2025030514073312.dist-info/entry_points.txt,sha256=oDWOW9SsBlk4Uejj1ftYPBxfhJ5ZJctb4JOUIG1rc-4,34
 my_test_code-0.0.1+2025030514073312.dist-info/top_level.txt,sha256=74rtVfumQlgAPzR5_2CgYN24MB0XARCg0t-gzk6gTrM,4
 my_test_code-0.0.1+2025030514073312.dist-info/RECORD,,
-

acceptance/cmd/patchwhl/script

@@ -6,7 +6,9 @@ trace $CLI selftest patchwhl my_test_code-0.0.1-py3-none-any.whl
 mkdir output original
 unzip -q my_test_code-0.0.1+2025030514073312-py3-none-any.whl -d output
 unzip -q my_test_code-0.0.1-py3-none-any.whl -d original
+rm my_test_code-0.0.1+2025030514073312-py3-none-any.whl
 
 # rename directory to match so that we can compare contents
 mv original/my_test_code-0.0.1.dist-info original/my_test_code-0.0.1+2025030514073312.dist-info
 trace diff.py original output
+rm -fr original

libs/patchwheel/patch.go

@@ -103,7 +103,6 @@ func patchRecord(r io.Reader, oldDistInfoPrefix, newDistInfoPrefix, metadataHash
 	if err := scanner.Err(); err != nil {
 		return nil, err
 	}
-	buf.WriteString("\n")
 	return buf.Bytes(), nil
 }