Avoid erroneous Q002 error message for single-quote docstrings (#1777)

Fixes #1775. Before implementing your solution I thought of a slightly
simpler one. However, it will let this function pass:
```
def double_inside_single(a):
    'Double inside "single "'
```
If we want function to pass, my implementation works. But if we do not,
then I can go with how you suggested I implemented this (I left how I
would begin to handle it commented out). The bottom of the flake8-quotes
documentation seems to suggest that this should pass:
https://pypi.org/project/flake8-quotes/

Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>

resources/test/fixtures/flake8_quotes/docstring_doubles_function.py

@@ -17,6 +17,15 @@ def fun_with_params_no_docstring(a, b="""
 """ """docstring"""):
     pass
 
+
 def fun_with_params_no_docstring2(a, b=c[foo():], c=\
     """ not a docstring """):
     pass
+
+
+def function_with_single_docstring(a):
+    "Single line docstring"
+
+
+def double_inside_single(a):
+    'Double inside "single "'

resources/test/fixtures/flake8_quotes/docstring_singles_function.py

@@ -13,11 +13,19 @@ def foo2():
 
 
 def fun_with_params_no_docstring(a, b='''
-    not a 
+    not a
 ''' '''docstring'''):
     pass
 
+
 def fun_with_params_no_docstring2(a, b=c[foo():], c=\
     ''' not a docstring '''):
     pass
 
+
+def function_with_single_docstring(a):
+    'Single line docstring'
+
+
+def double_inside_single(a):
+    "Double inside 'single '"

src/flake8_quotes/rules.rs

@@ -36,8 +36,8 @@ fn good_multiline_ending(quote: &Quote) -> &str {
 
 fn good_docstring(quote: &Quote) -> &str {
     match quote {
-        Quote::Single => "'''",
-        Quote::Double => "\"\"\"",
+        Quote::Single => "'",
+        Quote::Double => "\"",
     }
 }
 

src/flake8_quotes/snapshots/ruff__flake8_quotes__tests__double_docstring_docstring_doubles_function.py.snap

@@ -1,6 +1,6 @@
 ---
 source: src/flake8_quotes/mod.rs
-expression: checks
+expression: diagnostics
 ---
 - kind:
     BadQuotesMultilineString: single
@@ -45,10 +45,10 @@ expression: checks
 - kind:
     BadQuotesMultilineString: single
   location:
-    row: 21
+    row: 22
     column: 4
   end_location:
-    row: 21
+    row: 22
     column: 27
   fix: ~
   parent: ~

src/flake8_quotes/snapshots/ruff__flake8_quotes__tests__double_docstring_docstring_singles_function.py.snap

@@ -1,6 +1,6 @@
 ---
 source: src/flake8_quotes/mod.rs
-expression: checks
+expression: diagnostics
 ---
 - kind:
     BadQuotesDocstring: double
@@ -22,4 +22,14 @@ expression: checks
     column: 7
   fix: ~
   parent: ~
+- kind:
+    BadQuotesDocstring: double
+  location:
+    row: 27
+    column: 4
+  end_location:
+    row: 27
+    column: 27
+  fix: ~
+  parent: ~
 

src/flake8_quotes/snapshots/ruff__flake8_quotes__tests__single_docstring_docstring_doubles_function.py.snap

@@ -1,6 +1,6 @@
 ---
 source: src/flake8_quotes/mod.rs
-expression: checks
+expression: diagnostics
 ---
 - kind:
     BadQuotesDocstring: single
@@ -22,4 +22,14 @@ expression: checks
     column: 7
   fix: ~
   parent: ~
+- kind:
+    BadQuotesDocstring: single
+  location:
+    row: 27
+    column: 4
+  end_location:
+    row: 27
+    column: 27
+  fix: ~
+  parent: ~
 

src/flake8_quotes/snapshots/ruff__flake8_quotes__tests__single_docstring_docstring_singles_function.py.snap

@@ -1,6 +1,6 @@
 ---
 source: src/flake8_quotes/mod.rs
-expression: checks
+expression: diagnostics
 ---
 - kind:
     BadQuotesMultilineString: double
@@ -45,10 +45,10 @@ expression: checks
 - kind:
     BadQuotesMultilineString: double
   location:
-    row: 21
+    row: 22
     column: 4
   end_location:
-    row: 21
+    row: 22
     column: 27
   fix: ~
   parent: ~