Parameters
- network: "base" | "ethereum" | "arbitrum" | "polygon" | "arbitrum-sepolia"
 
Returns { 
    collateralTokens: string[]; 
    indexTokens: string[]; 
    isLong: boolean[]; 
}
an object with the list of collateral tokens, index tokens,
and whether or not the position is long
collateralTokens: string[]
indexTokens: string[]
isLong: boolean[]
Gets all viable combinations of collateral tokens, index tokens and whether the position is long or short