Dev Containers: Update 'GHC 9.8'

- Add HLS v2.10.0.0

.devcontainer/VERSION_MATRIX.md

@@ -5,7 +5,7 @@
 | GHC                           | Cabal[^1] | Stack[^1] | HLS                                                 |
 |:------------------------------|:----------|:----------|:--------------------------------------------------- |
 | latest<br>9.10.1<br>9.10<br>9 | 3.12.1.0  | ≥ 2.13.1  | latest<br>2.10.0.0<br>2.9.0.1<br>2.9.0.0            |
-| 9.8.4<br>9.8                  | 3.10.3.0  | ≥ 2.13.1  |                                                     |
+| 9.8.4<br>9.8                  | 3.10.3.0  | ≥ 2.13.1  | 2.10.0.0                                            |
 | 9.6.6<br>9.6                  | 3.10.3.0  | ≥ 2.13.1  | 2.10.0.0<br>2.9.0.1                                 |
 
 [^1]: built-in version; see [GHC musl > Version Matrix](../VERSION_MATRIX.md)

.devcontainer/ghc-9.8/devcontainer.json

@@ -5,6 +5,7 @@
     "context": "..",
     "args": {
       "GHC_VERSION": "9.8",
+      "HLS_VERSION": "2.10.0.0",
       "USE_ZSH_FOR_ROOT": "unset-to-use-ash",
       "SET_LANG": "C.UTF-8",
       "SET_TZ": ""