`cabal install` does not accept relative dirs in `--store-dir` (but `cabal build` does)

Installation aborts in the middle when a relative path is passed to `--store-dir`:
```
$ cabal --store-dir=. install hello
...
In order, the following will be built (use -v for more details):
- hello-1.0.0.2 (exe:hello) (requires build)
...
Configuring hello-1.0.0.2...
Error: cabal: expected an absolute directory name for --prefix:
./ghc-9.2.1/hll-1.0.0.2-1e2f3837

Error: cabal: Failed to build hello-1.0.0.2. The failure occurred during the
configure step.

$ tree
.
└── ghc-9.2.1
└── package.db
├── package.cache
└── package.cache.lock
```
In contrast.
```
$ cabal --store-dir=$PWD install hello
```
succeeds.

Would a simple fix be to turn the `--store-dir` into an absolute path just after parsing this command line argument?

This issue came up before, see https://github.com/haskell/cabal/issues/7130#issuecomment-715611796; in https://github.com/haskell/cabal/issues/7130#issuecomment-715903180 @phadej invites PRs. A systematic fix has been started in #6667 but is unfinished.

UPDATE: looks like I duplicated #7760.

Reproduce the issue with `cabal --store-dir=. install hello` and compare it with `cabal build` and an absolute store directory. Read the discussion in issues #7130, #6667, and the superseding duplicate #7760; done means relative `--store-dir` works for install without the configure-step absolute-directory error.

Written by the indexing model from the issue text.