🐛 "\ No newline at end of file" is not correctly handled

When the file does not end in a new line, diff emits a \ No newline at end of file line. Currently delta would just treat it similar to a normal unchanged line, but that causes problems when the diff section extends all the way to file end:

$ diff -u minus.txt plus.txt
--- minus.txt   2020-12-04 20:47:52.000000000 -0500
+++ plus.txt    2020-12-04 20:48:00.000000000 -0500
@@ -1,5 +1,5 @@
-key_0: value_0
-key_1: value_1
-key_2: value_2
-key_3: value_3
-key_4: value_4
\ No newline at end of file
+key_0: value_1
+key_1: value_2
+key_2: value_3
+key_3: value_4
+key_4: value_5
\ No newline at end of file

In this case, the minus and plus hunks should be matched together, but since the "no newline" message was in between, the minus hunk is marked as deleted:

$ delta -s minus.txt plus.txt --max-line-distance=1

comparing: minus.txt ⟶   plus.txt

│ 1  │key_0: value_0                  │    │
│ 2  │key_1: value_1                  │    │
│ 3  │key_2: value_2                  │    │
│ 4  │key_3: value_3                  │    │
│ 5  │key_4: value_4                  │    │
\ No newline at end of file
│    │                                │ 1  │key_0: value_1
│    │                                │ 2  │key_1: value_2
│    │                                │ 3  │key_2: value_3
│    │                                │ 4  │key_3: value_4
│    │                                │ 5  │key_4: value_5
\ No newline at end of file

Reproduce the case with diff -u minus.txt plus.txt and delta -s minus.txt plus.txt --max-line-distance=1 using files without trailing newlines. Trace the diff parsing and hunk-matching path; done means the minus and plus hunks remain matched together while preserving the \ No newline at end of file markers.