fix: Sphinx generated incorrect type references for display

When rendering a type reference link, the trailing backtick must be followed by
a non-word character; however the code generated array and union references that
followed this backtick directly with `[` or `)` respectively. This caused a lot
of warnings to be emitted by `sphinx-build`, and resulted in incorrect output.

This adds an escaped space (`\ `) after the backticks, which `sphinx-build`
correctly interprets as a non-word character, but results in no character being
emitted to the output - thus generating the desired output.

packages/jsii-pacmak/lib/targets/sphinx.ts

@@ -507,7 +507,7 @@ class SphinxDocsGenerator extends Generator {
         if (spec.isNamedTypeReference(type)) {
             const fqn = this.toNativeFqn(type.fqn);
             result = {
-                ref: `:py:class:\`${type.fqn.startsWith(`${this.assembly.name}.`) ? '~' : ''}${fqn}\``,
+                ref: `:py:class:\`${type.fqn.startsWith(`${this.assembly.name}.`) ? '~' : ''}${fqn}\`\\ `,
                 display: fqn
             };
         } else if (spec.isPrimitiveTypeReference(type)) {

packages/jsii-pacmak/test/expected.jsii-calc-base/sphinx/_scope_jsii-calc-base.rst

@@ -188,7 +188,7 @@ BaseProps (interface)
 
 
 
-   :extends: :py:class:`@scope/jsii-calc-base-of-base.VeryBaseProps`
+   :extends: :py:class:`@scope/jsii-calc-base-of-base.VeryBaseProps`\ 
 
 
    .. py:attribute:: bar

packages/jsii-pacmak/test/expected.jsii-calc-lib/sphinx/_scope_jsii-calc-lib.rst

@@ -282,7 +282,7 @@ Number
    Represents a concrete number.
 
 
-   :extends: :py:class:`~@scope/jsii-calc-lib.Value`
+   :extends: :py:class:`~@scope/jsii-calc-lib.Value`\ 
    :param value: The number.
    :type value: number
 
@@ -332,7 +332,7 @@ Operation
    Represents an operation on values.
 
 
-   :extends: :py:class:`~@scope/jsii-calc-lib.Value`
+   :extends: :py:class:`~@scope/jsii-calc-lib.Value`\ 
    :abstract: Yes
 
    .. py:method:: toString() -> string
@@ -424,7 +424,7 @@ Value
    Abstract class which represents a numeric value.
 
 
-   :extends: :py:class:`@scope/jsii-calc-base.Base`
+   :extends: :py:class:`@scope/jsii-calc-base.Base`\ 
    :abstract: Yes
 
    .. py:method:: toString() -> string