Remove some double blank lines

Author: ehuss

src/attributes.md

@@ -109,7 +109,6 @@ fn some_unused_variables() {
 
 r[attributes.meta]
 
-
 r[attributes.meta.intro]
 A "meta item" is the syntax used for the _Attr_ rule by most [built-in
 attributes]. It has the following grammar:

src/attributes/codegen.md

@@ -63,7 +63,6 @@ assumed to exist.
 
 r[attributes.codegen.target_feature]
 
-
 r[attributes.codegen.target_feature.intro]
 The *`target_feature` [attribute]* may be applied to a function to
 enable code generation of that function for specific platform architecture

src/attributes/debugger.md

@@ -86,7 +86,6 @@ When viewed under WinDbg, the `fancy_rect` variable would be shown as follows:
 
 r[attributes.debugger.debugger_visualizer.gdb]
 
-
 r[attributes.debugger.debugger_visualizer.gdb.pretty]
 GDB supports the use of a structured Python script, called a *pretty printer*, that describes how a type should be visualized in the debugger view.
 For detailed information on pretty printers, refer to GDB's [pretty printing documentation].
@@ -161,7 +160,6 @@ When the crate's debug executable is passed into GDB[^rust-gdb], `print bob` wil
 
 r[attributes.debugger.collapse_debuginfo]
 
-
 r[attributes.debugger.collapse_debuginfo.intro]
 The *`collapse_debuginfo` [attribute]* controls whether code locations from a macro definition are collapsed into a single location associated with the macro's call site,
 when generating debuginfo for code calling this macro.

src/attributes/derive.md

@@ -2,7 +2,6 @@
 
 r[attributes.derive]
 
-
 r[attributes.derive.intro]
 The *`derive` attribute* allows new [items] to be automatically generated for
 data structures.

src/attributes/diagnostics.md

@@ -492,7 +492,6 @@ The attribute should be placed on a [trait declaration], though it is not an err
 r[attributes.diagnostic.on_unimplemented.syntax]
 The attribute uses the [_MetaListNameValueStr_] syntax to specify its inputs, though any malformed input to the attribute is not considered as an error to provide both forwards and backwards compatibility.
 
-
 r[attributes.diagnostic.on_unimplemented.keys]
 The following keys have the given meaning:
 * `message` --- The text for the top level error message.

src/attributes/testing.md

@@ -11,7 +11,6 @@ enables the [`test` conditional compilation option].
 
 r[attributes.testing.test]
 
-
 r[attributes.testing.test.intro]
 The *`test` attribute* marks a function to be executed as a test.
 
@@ -55,7 +54,6 @@ fn test_the_thing() -> io::Result<()> {
 
 r[attributes.testing.ignore]
 
-
 r[attributes.testing.ignore.intro]
 A function annotated with the `test` attribute can also be annotated with the
 `ignore` attribute. The *`ignore` attribute* tells the test harness to not

src/attributes/type_system.md

@@ -8,7 +8,6 @@ The following [attributes] are used for changing how a type can be used.
 
 r[attributes.type-system.non_exhaustive]
 
-
 r[attributes.type-system.non_exhaustive.intro]
 The *`non_exhaustive` attribute* indicates that a type or variant may have
 more fields or variants added in the future.