remove more of the risc release (#9375)

# Description
<!--
Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.

Description of your pull request goes here. **Provide examples and/or
screenshots** if your changes affect the user experience.
-->

# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->

# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect -A clippy::result_large_err` to check that
you're using the standard code style
- `cargo test --workspace` to check that all tests pass
- `cargo run -- crates/nu-std/tests/run.nu` to run the tests for the
standard library

> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->

# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->

.github/workflows/release-pkg.nu

@@ -76,11 +76,6 @@ if $os in [$USE_UBUNTU, 'macos-latest'] {
             let-env CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER = 'aarch64-linux-gnu-gcc'
             cargo-build-nu $flags
         }
-        'riscv64gc-unknown-linux-gnu' => {
-            sudo apt-get install gcc-riscv64-linux-gnu -y
-            let-env CARGO_TARGET_RISCV64GC_UNKNOWN_LINUX_GNU_LINKER = 'riscv64-linux-gnu-gcc'
-            cargo-build-nu $flags
-        }
         'armv7-unknown-linux-gnueabihf' => {
             sudo apt-get install pkg-config gcc-arm-linux-gnueabihf -y
             let-env CARGO_TARGET_ARMV7_UNKNOWN_LINUX_GNUEABIHF_LINKER = 'arm-linux-gnueabihf-gcc'

.github/workflows/release.yml

@@ -64,9 +64,6 @@ jobs:
         - target: armv7-unknown-linux-gnueabihf
           os: ubuntu-20.04
           target_rustflags: ''
-        - target: riscv64gc-unknown-linux-gnu
-          os: ubuntu-20.04
-          target_rustflags: ''
 
     runs-on: ${{matrix.os}}