Update docs version dropdown for 1.12.7 release (#33091)

## Summary & Motivation

See title

## How I Tested These Changes

## Changelog

> Insert changelog entry or delete this section.

---------

Signed-off-by: nikki everett <nikki@dagsterlabs.com>

Author: neverett

CHANGES.md

@@ -6,7 +6,7 @@
 
 - Optimized performance of calculating partition keys for time window partitions with exclusions.
 - `timedelta` and `datetime` are now available via the `datetime` context when rendering components (Thanks, [@stevenayers](https://github.com/stevenayers)!)
-- `FreshnessPolicy` is now available via the `dg` context when rendering components. (Thanks, [@stevenayers](@https://github.com/stevenayers)!)
+- `FreshnessPolicy` is now available via the `dg` context when rendering components. (Thanks, [@stevenayers](https://github.com/stevenayers)!)
 - Assets may now be annotated with up to 10 kinds (limit was previously 3).
 - Arbitrary resource parameters may now be hidden in the UI by setting `json_schema_extra={"dagster__is_secret": True}` on the corresponding `Field` definition in the resource class.
 - The `dg docs` cli group has been removed. The `integrations` subcommand has been moved to `dg utils integrations`.

docs/docusaurus.config.ts

@@ -224,7 +224,7 @@ const config: Config = {
           lastVersion: 'current',
           versions: {
             current: {
-              label: 'Latest (1.12.6)',
+              label: 'Latest (1.12.7)',
               path: '/',
             },
           },