gptel-bedrock: Bump curl version requirement

While Curl 8.5.0 supports --aws-sigv4 parameter, its
implementation is buggy and versions prior to 8.9.0 trigger a "The
request signature we calculated does not match the signature you
provided. Check your AWS Secret Access Key and signing method."
error when interacting with Bedrock.

* NEWS (New models and backends): Update.
* gptel-bedrock.el (gptel-make-bedrock): Update Curl check.

Author: leezu

NEWS

@@ -51,7 +51,7 @@
 
 - Add support for AWS Bedrock models.  You can create an AWS Bedrock
   gptel backend with ~gptel-make-bedrock~, which see.  Please note:
-  AWS Bedrock support requires Curl 8.5.0 or higher.
+  AWS Bedrock support requires Curl 8.9.0 or higher.
 
 - You can now create an xAI backend with ~gptel-make-xai~, which see.
   (xAI was supported before but the model configuration is now handled

gptel-bedrock.el

@@ -617,8 +617,8 @@ MODEL-REGION - one of apac, eu, us or nil
 CURL-ARGS - additional curl args
 STREAM - Whether to use streaming responses or not."
   (declare (indent 1))
-  (unless (and gptel-use-curl (version<= "8.5" (gptel-bedrock--curl-version)))
-    (error "Bedrock-backend requires curl >= 8.5, but gptel-use-curl := %s, curl-version := %s"
+  (unless (and gptel-use-curl (version<= "8.9" (gptel-bedrock--curl-version)))
+    (error "Bedrock-backend requires curl >= 8.9, but gptel-use-curl := %s, curl-version := %s"
            gptel-use-curl (gptel-bedrock--curl-version)))
   (let ((host (format "bedrock-runtime.%s.amazonaws.com" region)))
     (setf (alist-get name gptel--known-backends nil nil #'equal)