Fix typos

Found via `codespell -L noone`

.github/ISSUE_TEMPLATE/bug_report.md

@@ -37,7 +37,7 @@ A clear and concise description of what you expected to happen.
 
 #### CLI output
 
-Add here the raw copy of some console output you were able to produce. Some exemple includes:
+Add here the raw copy of some console output you were able to produce. Some example includes:
 
 - The `mdedup` CLI invocation and its output:
 

.mailmap

@@ -1,5 +1,5 @@
 # Format is:
-#   Prefered Name <preferred e-mail>  Other Name <other e-mail>
+#   Preferred Name <preferred e-mail>  Other Name <other e-mail>
 #
 # Reference: https://git-scm.com/docs/git-blame#_mapping_authors
 

mail_deduplicate/cli.py

@@ -161,7 +161,7 @@ def format_help(
         default=BODY_HASHER_SKIP,
         type=Choice(sorted(BODY_HASHERS), case_sensitive=False),
         help=f"Method used to hash the body of mails. Defaults to {BODY_HASHER_SKIP}, "
-        "which does't hash the body at all: it is the fastest method and header-based "
+        "which doesn't hash the body at all: it is the fastest method and header-based "
         f"hash should be sufficient to determine duplicate set. {BODY_HASHER_RAW} use "
         f"the body as it is (slow). {BODY_HASHER_NORMALIZED} pre-process the body "
         "before hashing, by removing all line breaks and spaces (slowest).",

mail_deduplicate/mail.py

@@ -36,7 +36,7 @@ class DedupMail:
 
     Extends `standard library's mailbox.Message
     <https://github.com/python/cpython/blob/45ffab40e86777ecd49786a2c18c0c044ef0cb5b/Lib/mailbox.py#L1489-L1523>`_,
-    and shouln't be used directly, but composed with ``mailbox.Message`` sub-classes.
+    and shouldn't be used directly, but composed with ``mailbox.Message`` sub-classes.
     """
 
     def __init__(self, message=None) -> None:

mail_deduplicate/strategy.py

@@ -223,7 +223,7 @@ def select_all_but_one(duplicates):
 )
 """Groups strategy aliases and their definitions.
 
-Aliases are great useability features as it helps users to better reason about the
+Aliases are great usability features as it helps users to better reason about the
 selection operators depending on their mental models.
 """