Revert go-getter update (#26731)

The `go-getter` update in https://github.com/hashicorp/nomad/pull/26713 is not passing tests upstream (apparently https://github.com/hashicorp/go-getter/pull/548 is the origin of the problem but that PR did not ever run tests). The issue being fixed isn't a critical vulnerability, so in the interest of preparing us for the next release, revert the `go-getter` change but keep the Go toolchain update.

We'll skip go-getter 1.8.0 and pick up the next patch version once its issues are fixed.
Reverts commit 8a96929870.

.changelog/26713.txt

@@ -1,7 +1,3 @@
 ```release-note:security
 build: Update Go to 1.24.7 to address CVE-2025-47910
 ```
-
-```release-note:security
-build: Update go-getter to 1.8.0 which uses aws-sdk-go (v2)
-```

go.mod

@@ -55,7 +55,7 @@ require (
 	github.com/hashicorp/go-cty-funcs v0.0.0-20200930094925-2721b1e36840
 	github.com/hashicorp/go-discover v1.1.0
 	github.com/hashicorp/go-envparse v0.1.0
-	github.com/hashicorp/go-getter v1.8.0
+	github.com/hashicorp/go-getter v1.7.9
 	github.com/hashicorp/go-hclog v1.6.3
 	github.com/hashicorp/go-immutable-radix/v2 v2.1.0
 	github.com/hashicorp/go-kms-wrapping/v2 v2.0.18
@@ -184,19 +184,14 @@ require (
 	github.com/armon/go-radix v1.0.0 // indirect
 	github.com/aws/aws-sdk-go v1.55.6 // indirect
 	github.com/aws/aws-sdk-go-v2 v1.38.3 // indirect
-	github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.6.10 // indirect
 	github.com/aws/aws-sdk-go-v2/credentials v1.18.10 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.6 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.6 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/ini v1.8.3 // indirect
-	github.com/aws/aws-sdk-go-v2/internal/v4a v1.3.34 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ec2 v1.200.0 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ecs v1.53.8 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.1 // indirect
-	github.com/aws/aws-sdk-go-v2/service/internal/checksum v1.7.2 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.6 // indirect
-	github.com/aws/aws-sdk-go-v2/service/internal/s3shared v1.18.15 // indirect
-	github.com/aws/aws-sdk-go-v2/service/s3 v1.80.1 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sso v1.29.1 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.34.2 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sts v1.38.2 // indirect
@@ -248,8 +243,6 @@ require (
 	github.com/gookit/color v1.3.1 // indirect
 	github.com/gophercloud/gophercloud v0.1.0 // indirect
 	github.com/gorilla/mux v1.8.1 // indirect
-	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.2 // indirect
-	github.com/hashicorp/aws-sdk-go-base/v2 v2.0.0-beta.65 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/hashicorp/go-discover/provider/gce v0.0.0-20241120163552-5eb1507d16b4 // indirect
 	github.com/hashicorp/go-immutable-radix v1.3.1 // indirect
@@ -349,8 +342,8 @@ require (
 	golang.org/x/tools v0.35.0 // indirect
 	google.golang.org/api v0.217.0 // indirect
 	google.golang.org/genproto v0.0.0-20250115164207-1a7da9e5054f // indirect
-	google.golang.org/genproto/googleapis/api v0.0.0-20250818200422-3122310a409c // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20250707201910-8d1bb00bc6a7 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20250818200422-3122310a409c // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20250707201910-8d1bb00bc6a7 // indirect
 	gopkg.in/fsnotify.v1 v1.4.7 // indirect
 	gopkg.in/resty.v1 v1.12.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect