Bump TechDocs container to v0.3.5.

Signed-off-by: Eric Peterson <ericpeterson@spotify.com>

.changeset/techdocs-buh-bump-ts.md

@@ -0,0 +1,5 @@
+---
+'@backstage/techdocs-common': patch
+---
+
+Default TechDocs container used at docs generation-time is now [v0.3.5](https://github.com/backstage/techdocs-container/releases/tag/v0.3.5).

packages/techdocs-common/api-report.md

@@ -256,7 +256,7 @@ export class TechdocsGenerator implements GeneratorBase {
     config: Config;
     scmIntegrations: ScmIntegrationRegistry;
   });
-  static readonly defaultDockerImage = 'spotify/techdocs:v0.3.4';
+  static readonly defaultDockerImage = 'spotify/techdocs:v0.3.5';
   // (undocumented)
   static fromConfig(
     config: Config,

packages/techdocs-common/src/stages/generate/techdocs.ts

@@ -44,7 +44,7 @@ export class TechdocsGenerator implements GeneratorBase {
    * The default docker image (and version) used to generate content. Public
    * and static so that techdocs-common consumers can use the same version.
    */
-  public static readonly defaultDockerImage = 'spotify/techdocs:v0.3.4';
+  public static readonly defaultDockerImage = 'spotify/techdocs:v0.3.5';
   private readonly logger: Logger;
   private readonly containerRunner: ContainerRunner;
   private readonly options: GeneratorConfig;