Update Spades v.3.15.3: specify python version

[gallardoalba]

This PR specifies the Python version (3.9) since, as reported in ablab/spades#863, the current Spades version is not compatible with Python>=3.10.

Please read the guidelines for Bioconda recipes before opening a pull request (PR).

• If this PR adds or updates a recipe, use "Add" or "Update" appropriately as the first word in its title.
• New recipes not directly relevant to the biological sciences need to be submitted to the conda-forge channel instead of Bioconda.
• PRs require reviews prior to being merged. Once your PR is passing tests and ready to be merged, please issue the @BiocondaBot please add label command.
• Please post questions on Gitter or ping @bioconda/core in a comment.

Please use the following BiocondaBot commands:

Everyone has access to the following BiocondaBot commands, which can be given in a comment:

@BiocondaBot please update	Merge the master branch into a PR.
@BiocondaBot please add label	Add the please review & merge label.
@BiocondaBot please fetch artifacts	Post links to CI-built packages/containers. You can use this to test packages locally.

For members of the Bioconda project, the following command is also available:

@BiocondaBot please merge

Upload built packages/containers and merge a PR. Someone must approve a PR first! This reduces CI build time by reusing built artifacts.

Also, the bot watches for comments from non-members that include @bioconda/<team> and will automatically re-post them to notify the addressed <team>.

[BiocondaBot]

Artifacts built on CircleCI are ready for inspection:

Package(s)

Arch	Package	Repodata
linux-64	spades-3.15.3-h95f258a_1.tar.bz2	repodata.json

---

You may also use conda to install these:

• For packages on linux-64:

conda install -c https://177397-42372094-gh.circle-artifacts.com/0/tmp/artifacts/packages <package name>

---

Container image(s)

Package	Tag	Install with docker
spades	3.15.3--h95f258a_1	show curl -L "https://177397-42372094-gh.circle-artifacts.com/0/tmp/artifacts/images/spades%3A3.15.3--h95f258a_1.tar.gz" | gzip -dc | docker load

[bgruening]

@BiocondaBot please merge

[BiocondaBot]

I will attempt to upload artifacts and merge this PR. This may take some time, please have patience.