Bump minimum rust version to 1.33

Author: theduke

.travis.yml

@@ -6,8 +6,7 @@ rust:
   - nightly
 
   # Prevent accidentally breaking older Rust versions
-  - 1.32.0
-  - 1.31.0
+  - 1.33.0
 
 matrix:
   include:

_build/azure-pipelines-template.yml

@@ -10,10 +10,10 @@ jobs:
         rustup_toolchain: beta
       nightly:
         rustup_toolchain: nightly
-      minimum_supported_version_plus_one:
-        rustup_toolchain: 1.32.0
+      # minimum_supported_version_plus_one:
+      #   rustup_toolchain: 1.32.0
       minimum_supported_version:
-        rustup_toolchain: 1.31.0
+        rustup_toolchain: 1.33.0
   steps:
   - ${{ if ne(parameters.name, 'Windows') }}:
     # Linux and macOS.

juniper/CHANGELOG.md

@@ -17,7 +17,7 @@ This should not have any impact on your code, since juniper already was 2018 com
 
 ### Other changes
 
-- The minimum required Rust version is now `1.31.0`.
+- The minimum required Rust version is now `1.33.0`.
 - The `ScalarValue` custom derive has been renamed to `GraphQLScalarValue`.
 - Added built-in support for the canonical schema introspection query via
   `juniper::introspect()`.